Is this normal when sizing a Smith bullet?

[Maillemaker]

My sizing die came in from Lodgewood today. It is actually from Northeast Trading Co. It is a push-through sizer.

While the instructions say it has a gentle lead-in for the bullet, looking down the bore it has a rather abrupt chamfer from the lead-in bore to the sizing bore.

The bullets require a considerable amount of force to get through. My pure lead Smith bullets drop at .518, and I am sizing to .515. I pretty much have to "plunge" them through to get them to go - I can't slowly press them through.

And when they go through, they extrude a wing on the tail of each bullet, which I will now have to cut off, thus altering the bullet weights.

https://i.imgur.com/yoWkk8Ol.jpg
https://i.imgur.com/ibmlZxvl.jpg

Full-size pictures here: https://imgur.com/a/HEGU2OY

With 1:20 Tin:Lead bullets, I can't get them to go through the die at all. They jam in the sizer and I have to tap them back out from the top.

I'm using a Lee single stage press.

Should I be having this much trouble with this sizing die? My Lyman Lubrsizer knocks .578 bullets down to .576 without any problems at all.

Steve

[Maillemaker]

Also, I slugged the bore again with a sized pure lead bullet. The maximum diameter reading I'm getting off of the slugged bullet is .508.

So is .515 a good size to size to? Or should I be sizing even smaller? .512?

Steve

[Kevin Tinny]

Hello, Steve:

If GROOVE OD is .508", you are sizing too much.

With both Dewald's and Star/Magma sizers, trying to size over .002" creates issues.
The old Star instructions suggested hand lubing the first couple and then the lube pressed into the grooves by the sizer sufficed.

Since I dip AFTER SIZING, I lightly pre-lube before sizing with either bullet lube for minies or Imperial Die Sizing WAX for alloy bullets. Lubing reduces lever effort.

A drag-back fin shows over-sizing. Lube reduces the fin if not sizing too much.

Moulds should drop an unsized bullet at .001" over the SIZED diameter, IF want to size for shift or parting line.
I prefer BORED mould blocks with insignificant shift/parting lines that drop bullets at the GROOVE plus .xxx" diameter. If you get the mould's base cavity ID right, that ID can allow casting after shrink in an alloy that produces the desired OD.

One issue with sizing is the pushing punch OD vs. die ID. Minimal clearance of .0005" to no more than .001" helps prevent fins.

Getting the bullet base FLAT so the base sits SQUARELY on the punch tip prevents the bullet tilting slightly as it enters the die constriction. With minies that always seem to have a micro fin, I either burnish the base on a 1" thick plate or gently drag the slightly irregular base across 600 grit, ONE short amount. This does not remove metal in a material amount and has made no accuracy difference. It merely helps the bullet sit flat on the punch.

Regards, Kevin

[Maillemaker]

If GROOVE OD is .508", you are sizing too much.

The maximum reading I'm getting off of the slugged bullet is .508". That should be the groove diameter, yes?

So .515 is too small? What would recommend I size to? The bullet cast .518" in pure lead, and .522 in Tin:Lead alloy.


Since I dip AFTER SIZING, I lightly pre-lube before sizing with either bullet lube for minies or Imperial Die Sizing WAX for alloy bullets. Lubing reduces lever effort.

These were lubed before sizing. I also lubricated the punch with oil prior to starting. It helped, but not much. 1:20 bullets will not go through the sizer no matter what.

I guess the big question is what diameter bullet should I use in a .508" bore? I thought a couple thousand's over, so, .51 or so?

Thanks,
Steve

[Kevin Tinny]

Steve:
With .508" GROOVE plus .0015" = around .5095" - .5100" sized OD:

Not sure we are clear ---
If YOUR BORE's max GROOVE is .508", then max sized OD would be .510", which is way less than the other dim's you questioned.

I haven't found .0005" matters, much less can be easily maintained.
So anywhere from .001" to .002" "over" has worked in my original Smith regardless of alloy.

All that presumes your bore is ok.

VR/Kevin
.

[Maillemaker]

If YOUR BORE's max GROOVE is .508", then max sized OD would be .510", which is way less than the other dim's you questioned.

So you're saying I should be using a .510" bullet?

I can get a Lyman .512 sizer as they are in stock. Maybe I should try that.

Steve

[Maillemaker]

I just went and re-spun the bullet in the calipers. The max diameter I'm getting is .510.

So is .512 a good bullet dimension?

Steve

[Kevin Tinny]

Thanks, Steve:

.500" across lands IN your barrel, plus .005" deep grooves IN barrel = .500" +2X .005" =
.510" groove depth IN barrel. The reverse applies to bullet:

Your bullet max OD across "high" spot, which is the LAND OD, is .510" plus the .002" "OVER" = .512" as-cast OD.

Try the Lyman .512" sizer, BUT if you are trying to reach .512" with a bullet much OVER .514", there will still be extra sizing effort.

Ideally, no pun, an as-cast OD of .513" would be best and require sizing only .001" to achieve .512".
Might require a custom bored set of blocks, so try the best available diameter.

Lyman 515141 shortened one grease groove by John Bly might work. Get w him. He might have one on hand.
My Bly shortened 515's are out on loan for fit testing in two other rifles so I cannot get them to you.
Both cast .5155" for my ORIGINAL Smith bore in 30:1, lead:tin, so would cast approx .001" smaller in pure.

I would be happy to pull some .5155", 30:1's from my S&S ctg's and send to you.
Might save fussing time.

Lemme know. Tx.

VR/Kevin

[Maillemaker]

OK, the problem is the sizing die.

I borrowed Mark Hubb's .512 Lee push-through sizer.

Even with unsized, .518 pure lead, they can be pushed through, though it does require some effort. The 1:20 tin:lead cannot be pushed down the small in one go.

So I will likely have to do a two-step sizing to push these down from .518 to .512.

But the North East Trading Co. die just isn't very good, in my opinion. It has a very harsh chamfer that provides the change in diameter from the entry bore to the sizing bore. So it is much more unforgiving to an over-sized bullet.

The Lee sizer has a much gentler transition cone. Since they are about the same money, I'd go with the Lee.

I took all the pure lead bullets I had pushed through the NETO die and shaved their tails off. This took about .5 grains off of each bullet. I then pushed them through the lee .512 die. So, now I have some bullets I can shoot.

I believe I will get a Lee .515 and .512 push-through sizers. I can then two-stage size these bullets.

Steve

[Maillemaker]

.500" across lands IN your barrel, plus .005" deep grooves IN barrel = .500" +2X .005" =
.510" groove depth IN barrel. The reverse applies to bullet:

Your bullet max OD across "high" spot, which is the LAND OD, is .510" plus the .002" "OVER" = .512" as-cast OD.

Well, as-sized, right? I should be shooting a .512" diameter bullet in a .510" groove diameter bore.

Right?

Steve

[Maillemaker]

Well, my closest range was shut down due to C-19. I forgot my portable holes and it was an hour and fifteen minutes out to the unmanned range on the mountain and it was already 3pm, so no shooting today.

Steve

[Kevin Tinny]

Ok, Steve on .512" OD in a .510" groove depth bore.

I have done two-step sizing as a fit testing experiment to learn what dim is correct, but sizing over .002" is not the best approach, and it adds work steps.

Ultimately the correct OD CASTING has to be achieved so minimal sizing is needed.

R/Kevin

[Harry Gaul]

I am a fan of a small bullet. If the grooves are 510, I would shoot a 508. Scientifically, the law of physics demand that two things can NOT occupy the same space at the same time; bullet and fouling are competing for the same groove space. If they try, it is called an accident. There is guy on Facebook by the name of Robert Bradley. He makes a very nice sizer and pusher for an loading press (7/8 X 14) for reasonable amount of money shipped. I purchased two sizers from him. Be sure to mention that the lead in portion of the sizer should be larger than the finished diameter.

Back to physics. I am trying to shoot a second model , 50 cal , Maynard. People are telling me to shoot a 515. I tried that, and after three shots the fouling is so bad that the bullet actually hesitates in the barrel and then spits out at some unknown velocity and place. I switched to a 510 bullet and I can shoot maybe 20 to 25 rounds before cleaning. I am not a good shot but win a medal from time to time. If my eyes and nerves were better, who knows what kind of shooter I would be. Maybe not good, but it would certainly more fun.

True Blue and Diamond hard,
Harry
3rd US
03626v

[Michael Bodner]

But the North East Trading Co. die just isn't very good, in my opinion. It has a very harsh chamfer that provides the change in diameter from the entry bore to the sizing bore. So it is much more unforgiving to an over-sized bullet.


Steve,

A few years back, a whole batch of North East Trading Co sizing dies were made terribly... Basically, they lacked any taper and were simple two diameters. Made by a sub-contractor and John replaced them if you brought them to him... However, if you bought this second hand, you may be out of luck.

For future reference, Tom Crone makes OUTSTANDING dies. Mirror polished... I highly recommend his work...

-Boots

[Michael Bodner]

Steve,

I shoot an identical bullet in my Smith (my mold is Rapine). The mold is stamped .515 but it really tosses out 0.520. I size down to 0.517 (again, an poorly made 0.515 sizer)?

If I slug the barrel, the bullet gets pretty swaged down. The grease grove is greatly reduced. HOWEVER, the dang gun shoots like the bullets are laser guided... BTW: I'm casting with hard lead, about 7-8 BHN

So....

Although I won't dissuade you from exploring the 'best' diameter to cast/size based on the land and groove dimensions, I highly encourage you to simple cast some, size them slightly to get uniform dimensions (see other post about bad North-East sizer) and see how they group... YES, I know that everyone says 'Just try', but in this case, I'm encouraging you based on very similar dimensions for my Smith (Lands and grooves are way down near .505 range). BTW: I'm loading 31 grains 3f, plastic cases, and some grits on top of the powder to get the bullet over-all length longer (so bullet touches the rifling). When I close the breech, the bullet is pushed back and compresses the powder... I lube BEFORE sizing with MCM lube.

Of course, if you give up, I'll give you $300 for that crappy gun!! LOL

-Boots

[Maillemaker]

A few years back, a whole batch of North East Trading Co sizing dies were made terribly... Basically, they lacked any taper and were simple two diameters. Made by a sub-contractor and John replaced them if you brought them to him... However, if you bought this second hand, you may be out of luck.

Here is a picture of the bore of the NETO sizing die. Basically it looks like it has a simple 45 degree chamfer between the inlet and sizing bore.

https://i.imgur.com/GllCBGul.jpg
https://i.imgur.com/0lNd2Yul.jpg
https://i.imgur.com/hCCDWlkl.jpg

Full-sized pictures here: https://imgur.com/a/NqmrG9E

I bought it from Lodgewood, new. The box, however, says North East Trading Company.



Although I won't dissuade you from exploring the 'best' diameter to cast/size based on the land and groove dimensions, I highly encourage you to simple cast some, size them slightly to get uniform dimensions (see other post about bad North-East sizer) and see how they group... YES, I know that everyone says 'Just try', but in this case, I'm encouraging you based on very similar dimensions for my Smith (Lands and grooves are way down near .505 range). BTW: I'm loading 31 grains 3f, plastic cases, and some grits on top of the powder to get the bullet over-all length longer (so bullet touches the rifling). When I close the breech, the bullet is pushed back and compresses the powder... I lube BEFORE sizing with MCM lube.

Of course, if you give up, I'll give you $300 for that crappy gun!! LOL

Well, that's re-assuring, thanks! I believe when my .515 and .512 dies come in I will start with .515 and see how they do.

Steve

[bobanderson]

GUYS, GUYS, GUYS! Take a breath.

A civil war carbine is 50 caliber. The reason we use .515" bullets, or larger, is because the 50 caliber is the diameter of the bore across the lands, the tops of the rifling. The .515 is because each rifling groove is cut to a depth of five to eight thousandths. You cannot usually measure a slug pushed through the rifling because, with an odd number of grooves, your measuring tool is reading from the top of one land to the bottom of one groove. The reason we have an odd number of grooves is because you need to support the rifling cutter on the opposite side as you cut your grooves.
A thought occurs to me if you want to accurately measure your bore. Start with a set of minus plug gauges measuring .498, .499, .500, .501 and .502. Use these to find the land diameter of your bore. (I just tried to insert a piece of 1/2 cold roll steel into my Maynard 50 barrel. It was too tight, but it's possible plain steel bars are not exactly to size. Another possibility is to try a 1/2" drill bit.)
Anyways, then push a slug through as before and measure with a dial caliper. You should get somewhere between .505 and .510. Subtract the land diameter of your bore, say .500 from this second measurement, say .507 (or even .5075) and then multiply that by 2 to get your actual groove diameter. For instance, .5075 minus .500 equals .0075 times two equals .015 which gives you a bullet size of .500 plus .015 equalling .515. Because most cast bullets shoot better a bit oversized, size your bullets to .517.

Boy will I be glad when we can get back to shooting again!

[Maillemaker]

I modeled up the bullet cross section in Solid Edge:

https://i.imgur.com/qX5J3tql.png (https://i.imgur.com/qX5J3tql.png)

It is possible to get a good measurement across the groove in the bullet, and the groove depth in the bullet, and then use this with the diameter measurement - in spite of the odd number of lands and grooves - to determine the actual OD and ID.

Based on these dimensions, it appears that the groove diameter is .51, and the bore diameter is .50.

I believe I will start with .515 and see what happens.

Steve

[Maillemaker]

I put a 1/2" drill bit shank (measures .496" in diameter) in my bore and it just fits. I suspect my bore is .500.

Steve

[ms3635v]

Steve,

I have been using sizing dies made by Tom Crone (301-473-5699). They are high quality sizers that have a true, gentle lead in. I buy the dies he makes that thread into my RCBS Rockchucker press (7/8x14). I size my Moose Smith/Maynard mould from .520" to .518" with no damage to the bullet. This is the bullet I use in both my original Smith and my Second model Maynard.

[Hal]

I was in the cast bullet world before I got into black powder. Among cast bullet enthusiasts, the general consensus is that .003" is the maximum amount you want to size down a bullet. .002" is even better. It really doesn't matter if you do it in steps. There is a good chance you will deform a bullet by sizing it any more than .003", no mater how many steps you do it in.

Another general consensus is that bullets for breech loaders should be .001" to .002" over groove diameter. Anything under groove diameter requires obturation to fill the bore. If the bullet does not obturate (and unless they are pretty soft and there's a pretty hefty charge behind them, they won't), the gases forcing it up the barrel will blow past the sides of the bullet and can erode lead from the sides of the bullet. This is called "Gas cutting." This lead that is cut from the bullet has a nasty habit of attaching itself to the inside of the barrel, more commonly called "Leading". Granted, there is more than one cause of leading, but the number one cause is an undersized bullet.

[Maillemaker]

OK, I ordered a set of hole gauges from Amazon. It's basically a split sphere with a screw you can screw in and out to expand the spheres, giving two points of contact in a hole.

https://i.imgur.com/MTCpByYl.jpg

You screw the screw until the spheres touch on either side of the hole you are measuring, and then remove the tool and measure across the spheres with calipers.

I did this with my Smith bore. Since there are 3 lands and 3 grooves, this gives me the bore diameter + groove depth measurement. This dimension is .508".

Measuring on the slug that I pushed down the barrel, I'm getting about .005" groove depth. It's difficult to get a good measurement on the shelf of such a tiny feature in the lead.

This means my bore diameter is .503, and my groove diameter is .513.

https://i.imgur.com/NHOfEEUl.png

So, I believe .515 bullets should work fine in this Smith.

Note in the above diagram that the .263 groove width dimension does not determine the diameters - it has no effect on them whatsoever.

Steve

[Maillemaker]

By the way, I ordered a .518 and .512 custom sizing die from Lee about 2 weeks ago when I started this thread, and today I got notification that they have shipped.

Pretty good turn-around at the moment.

Steve

[Sven205]

By the way, I ordered a .518 and .512 custom sizing die from Lee about 2 weeks ago when I started this thread, and today I got notification that they have shipped.

Pretty good turn-around at the moment.

Steve

This is good to know! I've been looking at press mounted sizers but their 8 week wait time quote was what was stopping me on ordering the Lee.

I've been thinking I will make a mount for a single stage press to mount upside down so they drop into the hopper instead of pushing up into it.

[Maillemaker]

I've been thinking I will make a mount for a single stage press to mount upside down so they drop into the hopper instead of pushing up into it.

I have heard others do this also.

Steve

[Maillemaker]

Lee sizing dies in .518 and .515 came in today.

When I push through .515 directly, I get the slightest bit of flash on the bottom of the bullet.

When I push through the .518, it barely knocks any off.

I tried pushing .518 first and then .515, still get a tiny fin, so not worth double-sizing.

I'll take some pictures later.

I'm going to try to get to the range tomorrow. I'm going to do some load workups at .515 and .518, pure lead.

Steve

[Harry Gaul]

That is a lot of numbers. Just remember the laws of physics state that two things can not occupy the same place at the same time. You looking at groove, lands, lube, and fouling after the first shot. If you need something smaller, I have a 510, 511, and 512 sizer. I can sell you one hundred Lyman 515139 bullets of different sizes for $40 shipped. The bullets will be soft lead.

true blue and Diamond Hard,
Harry
03626v

[Maillemaker]

OK, all's good. After pushing 7 bullets through the sizer, it eased right up. All the rest pushed through with very little effort and no flash. These bullets size to .515 with no problem at all.

Steve

[Hal]

Steve,

If you are not already, lube them before sizing. You may already be doing this. If so, please disregard.

[Maillemaker]

Well, my first go, I lubed before sizing. I figured this way the grease grooves could be full and the sizer would wipe off the excess. But, I know from modern reloading that the lube can actually swage the bullet smaller. Also someone here suggested lubing after sizing. So, this go-around I lubed after sizing.

I dip-lubed. So-as not to have a big crust of lube on the bullets, I pre-heated all my bullets on the same hot plate that I melt the tin of lube in. Then I dip them, wipe their bottoms on a piece of wax paper, and set them aside to cool. Most of the lube runs off, with a bit being held in the grease groove due to capillary action. But the groove is not "full to the rim" of lube this way.

Steve

[Harry Gaul]

No one bit on my comment about bullet size and groove size and land size. In the world of the other muzzleloaders, they have a fouling shot and then "Clean" between shots for the best accuracy. During the Civil War, bullet was under size, gun went bang, hot gases, lead skirt expanded, engaged the rifling and the results was a fairly accurate shot. Then introduce the Williams Cleaner bullet with expanding zinc disc to scrape the barrel every so often (?) to "clean" the barrel of fouling. I am puzzled that shooters here are shooting a bullet that is one to two thousands over groove size and shooting well. Are we measuring correctly? Physics says that two things can NOT occupy the same space at the same time. If you do, that is why it is called an accident! With every shot, you are shooting a bullet, lube, and lube residue and fouling with a build up of fouling, shot after shot. Friction has to be building. Fascinating? Who am I to argue with success.

Here is link to a muzzleloading club in Missouri. It talks about a clean barrel, then the fouling shot and then cleaning between shots for accuracy.
http://www.gemmermuzzleloadingclub.com/

True Blue and Diamond Hard,
Harry
03626v

[Bruce Cobb 1723V]

Your right , muzzle loading bullets can't be compared to breech loading ones like a Smith. 2 different animals ..... Physics still apply ........ one expands, the other squashes down to occupy the area in a elongated space ... yes success works .... If lead wasn't so moldable / soft, we'd be in a world of hurt.

[John Holland]

And.......The "Williams Cleaner" as patented, was not intended to be a "Cleaner", but rather a "Better Projectile" using the Zinc Washer to form into the rifling, instead of relying on expansion of the Minnie Ball into the rifling. Later on it was tried as a "Cleaner Projectile" and found to be a failure in both applications. When issued, the soldiers frequently threw them away.

[Eggman]

As the pristine copies I bought from the metal detector guys attest.

[Maillemaker]

Harry I've kind of ignored your reply because I can't figure out what you are trying to say.

Obviously two things can't occupy the same space, and in shooting, they don't. The bullet deforms to fit in the available space.

So, what are you trying to describe?

Steve

[Harry Gaul]

My numbers might be slightly off, but the concept is that good shooters are shooting a bullet that is oversize to the measurement of the groove. If I understand the concept of this thread, many of the breech loaders shoot a bullet that is one to two thousandths over groove size, not land size. In your 50 cal Smith, what is the groove size, what is the land size, and what is the bullet diameter size? In theory a 515 bullet should not shoot well in a barrel with a groove size of 510. The pieces of the physics puzzle does not compute. Assuming a groove size of 510 and the bullet is 515 plus lube plus fouling shot after shot after shot, you are assuming a frictionless situation. My understanding is that there is no friction in a vacuum. Even air molecules cause friction to slow down a moving bullet. In my own experience I shoot an original 50 cal Maynard. The collective wisdom was to shoot a 515 bullet. The first shot was a hit, and the second was a hit, and the third shot was a hit. By the fourth shot, the bullet would travel down the barrel, and friction would take over, and the bullet would "appear" to stick in the barrel, but there was enough inertia left in the bullet to have the bullet spit out at some unknown velocity and location resulting in a miss and unsafe experience. I could feel the bullet "sticking" in the recoil. In the old days I shot a Burnside with a relined barrel. The bullet was a Rapine 54 cal, and the reline was one thousandth oversize. In general, the Carbine shot OK, but the brass cartridges were so expensive that I sold the Carbine for a repro Smith.

I understand the physics of the minie being undersized, but the oversize breech loader bullet continues to puzzle me. Again, your are talking 510 groove size, the land size 500, 515 bullet size, lube, and fouling shot after shot, little and no friction, and shoot well (?) confounds my scientific mind. Again my numbers might be a little off but the concept remains the same. That is the basis for my statement that two things can not occupy the same space at the same time. The again, who am I to argue with success. I suspect the measuring of the lands and grooves is not accurate.

True Blue and Diamond Hard,
Harry
03626v

[Maillemaker]

I bought and received a .500 plug gauge, it and fits tightly in the bore. It's within a couple of thousandths.

I also used a hole gauge, as I showed above, to find the dimension from groove to land. That dimension is highly repeatable and accurate - .508. This is the diameter of the bore plus the depth of one groove.

Measuring the groove depth on a bullet slugged through the bore gives me about .005, though it is hard to get an accurate measurement on such a small shelf in the lead.

That means my bore diameter is .503, and my groove diameter is .513.

So, a .515 bullet should work, being only a couple of thousandths oversize.


By the fourth shot, the bullet would travel down the barrel, and friction would take over, and the bullet would "appear" to stick in the barrel, but there was enough inertia left in the bullet to have the bullet spit out at some unknown velocity and location resulting in a miss and unsafe experience. I could feel the bullet "sticking" in the recoil.

Initially, I was only brushing between courses of fire. Mostly because I do not yet have a proper .50 cleaning jag yet. I've got a jag that will fit with a brush, but even with one thickness of patch it tears the patch.

Anyway I brushed after every 5 shots. After about 25 shots, I noticed, looking down the barrel from the breech end, that there was darkness on the last 1/3 or so of the barrel. It may well be that my bullets were running out of lube - there was none on the crown after shooting.

The way I lubed these was I sized first, then dip-lubed pre-heated bullets. Thus most of the lube ran out of the grease groove. I believe what I will do next time is not pre-heat, so that more lube sticks in the grease groove, and then run them through the sizer again to wipe off the excess lube. This should leave me with fully-packed grease grooves.


That is the basis for my statement that two things can not occupy the same space at the same time.

I see what you are saying now. But I slugged the barrel with a .518 bullet. The tail of the bullet looks like a star from the lands pushing lead out the back of the bullet, but the lead, being soft, will give way to the barrel. I imagine there will come a point where the gun explodes before the lead gives way, but I wouldn't think .005" of interference would do that. I bet even if I shot the bullets unsized at .518 they would go. I feel like .515 is probably better though. A bullet slugged through the bore will pass through the .515 sizing die, so it's for sure that the groove diameter is smaller than .515. The slugged bullet will not pass through a .512 sizing die, and I can see that it is hitting the high spots on the bullet only (made by the barrel grooves). So I think the barrel must be about .513 groove and is probably about .503 bore.

Steve

[Hal]

Harry,

I explained the conventional wisdom several posts ago. You can choose to believe it, or don't. It really doesn't matter to me. I too ignored your post, because I didn't want to argue. If what you do works for you, then by all means, keep doing it. I will continue to do what practically all cast bullet shooters do, whether they shoot black powder, modern automatic pistols, or high powered rifles, and that is slightly oversized bullets.

[Muley Gil]

Steve, you should be able to find a.50 brass jag that will fit a shotgun cleaning rod at most any decent sporting goods store.

[Maillemaker]

Yeah I dug through my boxes of gun cleaning kits and found one that will work for now.

Steve

[Bruce Cobb 1723V]

If anyone wants to do an experiment, you will find you can take a slightly undersized round 69 bullet (Unpatched) in a rifled bore and shoot it. When you retrieve it, it will have the rifling showing on it. Pressure is deforming and flattening it into the grooves .... I guess that darn ol physics is at it again.

[Harry Gaul]

Part of the answer is Inertia. An object at rest will stay at rest, and an object in motion will stay in motion unless the object is subjected to an outside force. Load, bang, explode, hot gases, lead deforms, picks up rifling, spins, hit a target, pieces fall to the ground (Gravity). Team commander calls time and the family behind the fence goes wild. Well done all around.

True Blue and Diamond Hard,
Harry
03626v

[bobanderson]

Part of the answer is Inertia. An object at rest will stay at rest, and an object in motion will stay in motion unless the object is subjected to an outside force. Load, bang, explode, hot gases, lead deforms, picks up rifling, spins, hit a target, pieces fall to the ground (Gravity). Team commander calls time and the family behind the fence goes wild. Well done all around.

True Blue and Diamond Hard,
Harry
03626v

Nailed it, Harry. Except some times the horn blows first.

[johnsymborski]

I've shot three Smiths over the years. The first was an original with a max bore (bottom of groove to bottom of groove) of around .518 - typical for an original bore. I used a .520 Smith round (20:1) sized to .519 with a Lyman Lubrisizer - no problems. The second was a repo. with a .515 max bore Rapine used to sell a mold at the time for repros (.515 dia.) that would come out of a hot mould at .517 and I sized them .516 - no problems. Now I have an original relined by Hoyt and it is .515 max. i use a Lyman 515139 mould (355 grain weight round) that comes out hot at .517 and is sized to .516 - no problems. (30 grain 3F powder charge, press a styrofoam wad over that plus a dab of lithium grease)

So the challenge is that your barrel at .510 is on the low side. No way you should try sizing a .520 round. You can get Lubrisizer dies by the thousandth from S&S (and at least one other), and lubrisizers push the base of the round into the die, which works better (and lubes at the same time). Still, a .517 round has too much meat on it. You can get a two-cavity mould from Accurate bullet molds in any O.D. you need, if there is not a suitable profile on their website already. .512 is what you need - then size to .511

Another alternative is to reline the Smith to .515

Johnny

[Maillemaker]

Hi Johnny,

As I said above, I believe my bore is .503, and my groove diameter is .513.

I think .515 will work fine, and they shot great in the black Smith tubes with 33 grains 3F Goex.

Steve