Burnside Carbine Question

[patio]

Wanting to maybe shoot a Burnside carbine purchased many years ago. Have a question concerning the breechblock. Without a cartridge the rear block which houses the nipple is against the front block.

http://https://i.imgur.com/EZ61Skq.jpg?1

When a cartridge is chambered and the breechblock is closed, will the rear block move back creating a gap between the front block and rear block and move against the receiver and close the gap that was between the receiver and the rear block?

http://https://i.imgur.com/xEFLUmN.jpg?1

Any good books out there on shooting the Burnside?

Thank you very much,

Pat

[Jim Brady Knap's Battery]

The rear portion of the block assembly is spring loaded to the front to help with extraction of fired cartridges. This is why the chamber and cartridges are tapered. The concept is that when the block is opened the spring loaded rear portion will move forward pushing the tapered cartridge free of the tapered chamber. Works OK until things carbon up. The carbine should not be fired without a proper cartridge.

[patio]

Seems to me that you would want the rear portion of the block touching the receiver when a case is in the breechblock and in battery. When the cartridge is fired, this contact would stop any rearward movement of the breechblock by the receiver. If there is no contact by the rear portion of the block and the receiver, something has to hold the block in place before the rear portion contacts the receiver when the cartridge is fired. The rear portion of the block would be driven back (forcibly?) until contact is made with the receiver. I am thinking that a correctly headspaced cartridge should push the rear portion of the block against the receiver. There should be no further rearward movement of the rear breechblock when a cartridge is in battery. If it doesn't there could be problems with split cases, a peened rear breechblock or receiver, and maybe accuracy?

Thank you,

Pat

[John Holland]

Like Jim said, the rear section is spring loaded, remove the rear breech block section and look at it. You will see that there is a cone shaped Platinum insert in the face of it. Your cartridge has to fit that contour perfectly. If it doesn't you will irrevocably damage it by firing an ill fitting cartridge. The rear section of the breech block works as a cam when the lever is pulled down after firing, by being pushed forward by the arc in the frame, which in turn breaks the cartridge case free from the tapered shape into which it sits. To remove the rear of the breech block you will have to rotate the small spring loaded piece, that holds it in place, to the left. This action will hold the spring in the compressed position thereby allowing you to slide the rear section backwards out of the breech block proper. This was part of the assembly and cleaning process for a Burnside Carbine.

[patio]

My observation is that the rear breach section has two purposes. The first one is that it is a "locking shoulder" that presses against the receiver and prevents rearward movement of the rear breach section when the cartridge is fired. The second purpose is what you and Jim have stated - when the breech is opened the rear breach moves forward under spring tension and it acts as an ejector to facilitate removal of the fired case.

In my first picture, the gap between the rear breach section and the receiver is about .080". When an empty cartridge is inserted in the breach and the breach rotated into battery, I am thinking that the gap should be minimal as to restrict rearward movement of the rear breach upon firing. I am guessing that .010" would probably be the most that I would want. Less would probably be better. Any thoughts on this?

Regards,

Pat

[Jim Brady Knap's Battery]

Well said John. Also I noticed that without a proper length case the nipple will not be positioned properly under the hammer nose.

[John Holland]

The movable section of the breech is supposed to bottom out against the frame when fired. The spring tension does not break the cartridge case free after firing. The case is broken free by the cam action of the frame against the movable section when the breech is opened. The spring tension is only to keep the movable section from falling out and getting lost when the breech is opened.

[patio]

Received some nylon cases for my carbine. Placed an empty case in the chamber and closed the action. The moveable breach moved against the receiver. There is no play between the moveable breach and the receiver now. There should be no or very little rearward motion of the moveable breach when fired. The headspace on this carbine seems to be good. Here is a picture of the empty case in battery.

http://https://i.imgur.com/gfLJBqD.jpg
(http://https://i.imgur.com/gfLJBqD.jpg)

Made a cerrosafe cast of the bore at the chamber end. The casting measured .552 in diameter. Ordered a .553 dia. 390 gr Burnside mold to try. Mold should be done in 3 weeks.

Next step will be to make a case holder that will fit a rockchucker press. Will use this holder to keep the cases steady and supported while seating wads (if necessary) and the bullet.

This is fun stuff!

[Hal]

.552 sounds awfully small, but if that's what it is, then that's what it is. Perhaps Carolina Reb will chime in here, but I was thinking .560?

[John Holland]

The original Burnside field mould casts a bullet which is 0.564" in diameter. The Burnside, like the Ballard, has a gain twist. Shooting a gain twist is a challenge because there will be a very narrow window of load combinations that will shoot accurately. That's my experience, anyway.

[patio]

To be honest, my expectations of the groove dia. were at .556 plus. The chamber end cast was done twice. The measurement of the groove depths measured by a micrometer from a low of .5510 to a high of .5518. Wanted to make absolutely sure that this was correct. Took a pure lead minie ball and carefully hammered it into the muzzle end about .100" deep. Carefully pulled it out and measured. High of a little under .552 using my micrometer. Used a dial caliper also to make sure that I wasn't misreading my micrometer -.552.

Thoughts are that there are (of course) tolerances in the land and groove diameters. Mine is probably towards the low end. Can't really say for sure as this is the only barrel I have to measure.

Hopefully others will share their experiences.

Thank you for your replies.

[Hal]

3 groove rifling is hard to measure.

[John Holland]

The Burnside Carbine has a 5 groove bore which, like a 3 groove bore, is also not able to be measured with a common Micrometer or Vernier, so I don't know how Patio did it.

[patio]

Mine is 6 groove. Counted the grooves by marking each one with a magic marker. Came up with 6.

Regards,

Pat

[EPPS1919]

Had mine Relined by Hoyt and It's .547 dia 5 grove had it checked with a 3 sided mic


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[John Holland]

Very interesting, I've seen a lot of Burnsides, but never a 6 groove!

[patio]

Bought this carbine in the mid 70's at the swap meets in WCH, Ohio from a guy by the name of Jack Lewis. He told me that it was a civilian model due to the lack of a saddle ring bar and sling swivel in the buttstock. The buttstock is cut out for the sling swivel and has the base of the swivel present but no swivel. No inspectors marks in the wood. Breechblock is matching to itself but not the receiver. Haven't taken it apart in many years but think none of the numbered parts matched. Barrel under the handguard has a P proof and the receiver has the same P proof. Can't see a seam in the barrel in the crown area which could be indicative of a reline. Could be very good workmanship but would think there would be some evidence of a seam if relined.

[Hal]

Maybe it was 5. I knew it was an odd number. Been a while since I looked at that, but I know I could never get a good slug measurement on mine, much to my chagrin.

I am a firm believer that bullet fit plays a big role in accuracy as well as whether or not you get leading of the bore. The bad thing on Burnside is that the case will kinda dictate the maximum bullet diameter. Unless you can machine or swage it open, you can only get so big a bullet in there. One thing I ran into was that the action crimps the thin lip at the mouth of the cartridge and gave me an inaccurate measurement of the actual size. I was measuring something like .556 on the case mouth and sizing the bullets accordingly. I found that opening that case mouth a bit would allow a .560 bullet to fully seat, so obviously the case is larger further down inside than the crimped lip I had been measuring. At this point, I believe I will be buying a new mould to take full advantage of this.

[patio]

Received my mold yesterday. That was quick. Unfortunately, don't have any handles yet. Company is Accurate Molds in Utah.

http://https://i.imgur.com/q6KwaL9.jpg
http://https://i.imgur.com/4sz4F1B.jpg?1
http://https://i.imgur.com/vZazIcm.jpg?1

[patio]

Got around to casting some bullets today. With pure lead, they are coming in at .5547 and weigh 396 gr. Was able to thumb press (with resistance) the bullet into the nylon case. The bullet bottoms out in the case at the lower part of the case neck radius. Put the case in the chamber and closed the action. Could feel resistance when the action closed as the bullet was engaging the rifling. In my opinion, this is good for 2 reasons. The first reason is the case may loosen a bit after firing. The bullet being forced against the rifling will keep the bullet seated and bottomed out to its proper depth in the case. The second reason is bullet obturation - the deformation and expansion of the bullet base by being smacked in the a$$ by the charge of burning black powder. For my rifle, obturation probably won't matter as my groove dia. is on the tighter side. My barrel will probably have to act as a sizer and swedge the bullet down a little in diameter.

Back in the days of the Great Rebellion, how were rifles with varying bore/groove diameters able to achieve accuracy with a cartridges of varying tolerances in bullet diameter? I think the answer is getting the bullet to obturate so it fits and seals to the groove diameter of the bore.

Hal, your .556 dia bullet is probably ok. How to get the bullet to obturate and fit your groove dia will be the challenge.

For reference, please read Spencer Wolf's book on shooting the trapdoor .45/70 Springfield. The groove diameters of the .45/70 are all over the place too. Bullet obturation took care of the varying groove diameters. Getting 2 ft groups at 50 yds is no fun. Getting 4" groups with the same rifle at 100 yds is. Ask me how I know.....


http://https://i.imgur.com/hP8dcrf.jpg

[mgmradio]

During the war , the carbine bullets were usually made larger than the average groove diameter of the guns. The Burnside bullets usually fall in the .556-562 range for originals. Base obduration wasn't really necessary as as the bullet was 2+ thousandths over grove diameter and was swaged down when traveling down the bore.
Your Burnside should shoot well out to two hundred yards, after that they get a little loose like a round ball gun.

[ms3635v]

A teammate has been shooting a Burnside for the last twenty-five years. He started shooting it with a .56 caliber roundball. When Rapine moulds made a conical that was very similar (also in .56 caliber) he tried it. The bottom line was the roundball was far superior in accuracy than the conical. We just competed last weekend in a MA Region carbine match and teammate used as usual and had sixteen hits using the roundball and the nylon/plastic cases. His Burnside hangs in there with Smiths and Maynards.

[patio]

Loaded 5 rounds. Starting with 40gr of 1 1/2F Old Eynsford. Accurate Molds 390B bullet. Dipped the bullet in lube to the case neck after the bullet was seated. Need to replace the nipple before firing.

[Harry Gaul]

Many years ago when bitten by the NSSA fever, I decided to rebuild and shoot a Burnside. It was one of the those "labors of Love" which is definitely part of the NSSA experience. I bought a decent Carbine and a crappy barrel and had the crappy barrel relined by Bobby. I saved the original barrel for resale options. There was a Rapine mold. I figuratively "sold a kidney" to buy the necessary brass cartridges and original replacement parts whether I needed them or not to compete in Individuals and team. There may be a few original parts in the deep bowels of my shooting box waiting for the Call? The Carbine shot reasonably well, but my Team mates were banging away with "the" Smith so I sold the Burnside and never looked back. Smith Carbine is the way to go. The molds are everywhere; cases come in brass, aluminum, and plastic, blue, gray or black at reasonable cost. The Maynard shooters just grasped in horror. Did you hear it? I heard it. If you bought a Burnside to shoot in competition, you have the NSSA fever real bad and the only cure is to bang away at paper and breakable targets after the virus thing has run its course.

TBDH,
Harry
03626v

[Dheisey#7003]

Harry wa the reason I bought a Burnside, and I also later sold mine for a Smith...It is a really interesting carbine and unusual, but trying to get it accurate was out of my wheelhouse.

[CAGerringer]

"It is a really interesting carbine and unusual, but trying to get it accurate was out of my wheelhouse."

OMG. I bought a museum quality 1865 version Burnside back in the mid 80's. It was beautiful. The most exquisite example of 1800's machining capabilities that I'd ever seen. It was the 80's and there weren't a lot of stuff to make this work. I had brass cases that would lose their lips after 5 or 6 shots. My mold was some god awful Dixie Gun Work thing that had no sprue cut off. I had to nip it with pliers and file it smooth. Even with all of this, I loved this gun, but as you're guessing, I couldn't hit diddley. So I ended up selling it. I wish I had had the Neoprene cases and a damned good mold. I'd probably still be struggling to get this bad boy to shoot!!!
Respectfully,
C.A. Gerringer
Old Dominion Dragoons

[EPPS1919]

Moose Molds makes a new Burnside 2 cavity mold that shoots pretty good in mine


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[EPPS1919]

9500


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[Carolina Reb]

Back in the 1980s, my first breechloading skirmish carbine was a nice Burnside with a perfect bore. It shot the Dixie bullet very well after I modified the mold with a sprue cutter. That Burnside was my go to carbine for about 5 years, but in a moment of weakness, it got sold. Burnside #2 was in great shape, but the breechblock was from another gun. It blew out cases on the first shot, every shot, so that one didn't stay long. I now have Burnside #3, which is a 4th model without the guide screw. It too has an almost perfect bore. This is the most frustrating carbine I ever owned. It will shoot a great group, and then at the next skirmish shots go all over the place. I've tried 4 or 5 different bullets. The Rapine bullet invariably shoots lousy. Round balls group great, but in 5 shots there are always one or two flyers, and they aren't even close. The best bullet has been the Accurate Molds 56-390A. When the Ol' General is smiling down on me, his carbine shoots great. But when he's feeling dyspeptic, things don't go so well. One of these days I'll figure it out! Two things that did help quite a bit were making a cartridge loader like the Harmon Maynard loaders, and annealing the case mouths. Getting all the bullets sized, seated straight and crimped consistently was definitely a step in the right direction.

[EPPS1919]

The Rapine shot like crap in my gun to I?ve got a Tennessee bullet mold that shoots just as good as the Moose molds bullet


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[spadegrip]

I don?t see a Burnside bullet on Moose?s website. Is it called a Burnside mould?

[EPPS1919]

You might give them a call I got the first test one they made to try out


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[noonanda]

I just got one of the Accurate molds, gonna try to cast up some bullets today

[johnsymborski]

Loaded 5 rounds. Starting with 40gr of 1 1/2F Old Eynsford. Accurate Molds 390B bullet. Dipped the bullet in lube to the case neck after the bullet was seated. Need to replace the nipple before firing.

Are nylon cases still available? I tried the brass ones they were selling in recent years, and the overall case lengths were a tad short - the 'swell' near the casemouqth (gas seal) does not appear as wide as brass cases that used to be available. The result was that the receiver was driven back a little when fired (the slider holding the nipple was designed to accommodate slight variations in case OAL ?), and this caused swelling and failure at the case mouth. What I did was to lathe cut .030 wide copper rings off nominal 1/2 plumping pipe, then soldered one on the back side of the 'swell' to get a better fit. Also I soldered .030 thick #8 brass washers onto the back of the cases. Result: a perfect fit for my model 5 Burnside, and the cases hold up fine ... but this is a lot of trouble (and cost) to go through. .562 round ball w/ 37.5 gr. 3F hit all in the black at 50 yards. I'm still trying to find a conical round that will equal that, but so far the groups have been larger than with round ball.

This is a work 'under development', as my "go to" carbine is an original Smith handed-down through several owners in my unit (it was a 'put together' gun as the serial #s are different on barrel, receiver and inside the removable side plate), but it shoots well enough that I'm not embarrassed.

[EPPS1919]

Logewood sells the plastic cases They work good. Moose molds just started making a Burnside mold that shoots very good in my gun


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[John Holland]

Respectfully, the statement about the design of the Burnside action "...the slider holding the nipple was designed to accommodate slight variations in case OAL..." is incorrect. The actual purpose of the spring loaded block is to break the case loose in the chamber when the breech is opened after firing. The "arc" design of the rear interior of the frame acts as a cam to push the cartridge case slightly forward. It was designed like this because the original cases were drawn from thin brass and when fired they formed tightly to the chamber cavity and, without the cam action, were nearly impossible to remove. This is also why the Burnside cartridge was designed with a full taper, because it only took a 1/16" of forward movement to break it completely free from the chamber.

[Harry Gaul]

You learn something new almost every day on this forum.

True Blue and Diamond Hard,

Harry
03626v

[johnsymborski]

BTW, I've figured out that the brass Burnside cartridges offered today are either made from another source or from a different NC program than the cartridges sold some years ago! A Burnside cartridge needs to be long enough to push the spring-loaded piece in the back of the action against solid metal, AND the geometry around the case mouth needs to be correct. Just look at a picture of an original Burnside round and you will see a generous 'swell' behind the case mouth to fill the action profile AND the gap between the barrel and the action when a round is loaded. Pictures of old Burnside brass also show this geometry. More than one supplier STILL use this picture, but the cases sold these days are a little shorter AND the 'swell' near the case mouth is no longer wide enough. What is being sold does not correspond to the pictured production previously offered. THAT is why I've had to solder on a brass washer to the base of my brass cartridges - then test fit and file as needed to get an OAL of 1.870 +/- .005. I also must lathe cut .030 copper rings from 1/2 plumbing tube and solder them on the rear side of the 'swell' near the case mouth so to fit the geometry of the action better. This is a lot of trouble, ergo I've ordered some nylon cases. This also explains why some people have had a long life and very many firing from their brass (since it is likely that brass is the 'old' style), and why many others report rapid swelling and cracking (as I experienced). I figured out a solution (with a lot of trouble) so I wouldn't wreck more of my brass cases that cost me $4 each (at the National). Also, I had to hand ream the inside of the case mouth to .562, because That is the side needed for a conical round to swage properly to the bore without excessive 'blow-by'. The nylon cases can fit over a nominal .560 round because they have 'give'. Brass cases (as made) only take .556 or so rounds, which have too large a pattern on the board when fired.

[Eggman]

the spring loaded block cam action
Long time since I owned a Burnside. Remember the cam action --- don't remember any spring.

[Steve Weems]

Johnsymborski? after reading your discussion about Burnside cases I was curious about some I had left in my miscellaneous bins and it turned out i had mostly the long ones. The mouths were running maybe .555. So if I get lucky and acquire another Burnside I know which ones to work with. Thanks for the education.

[Hal]

Eggman,

The cube shaped block at the rear of the Burnside breech block is retained by a spring loaded tab. You can flip the tab around out of the way and then remove the cube shaped piece for cleaning.