Maynard Carbine bore size

[remington1858]

Have any of you guys seen this. My Maynard Carbine slugs out to .508 Diameter. This is tapered down quite a bit from the chamber, but I'm not sure if this is normal? Thanks.

Wes

[RangerFrog]

Have any of you guys seen this. My Maynard Carbine slugs out to .508 Diameter. This is tapered down quite a bit from the chamber, but I'm not sure if this is normal? Thanks.

Wes

That sounds kinda tight to me, Wes. I would expect something like a .515-.520" or even bigger. Just my experience, so wait for more conclusive from PJ or others before you get too excited.

Froggie

[John Bly]

It is a three land and groove barrel. It sounds to me like you're measuring from the bore to one groove. The bore should be near .500, add .008 for the depth of one groove and there is your .508. Double the .008 to .016 and add it to the .500 for the slug size of .516 which is more nearly the proper size. The groove diameters generally run from about .515" up to .520"

[ms3635v]

Wes,

I have two original 2nd Model Maynards and they both shoot .518" diameter bullets (sized down from a .520 diameter bullet) weighing 350 grains. Maynards are extremely accurate when you get a bullet that fits your bore correctly.

[Edwin Flint, 8427]

Might he have one of the repros?

[remington1858]

It's original. I am sending the slug off to someone with the proper measuring devices. It is hard to get convential dial calipers on the both grooves at one time. Thanks to all who replied.

Wes

[William H. Shuey]

I have an original Maynard and slugged the barrel and measured the dia. on a comparator at work, was .518".
The Jensco replacement barrel that I shoot is .515".

Bill Shuey

I have also found some Maynard bores to be small. I have an original that slugs the groove diameter at 0.510, so obviously the bore diameter is less than that.
As far as correctly measuring the diameter of a 3-groove slug; when you put the slug in your mic, give it a turn. That will expand the jaws out to the maximal groove diameter. (I assume that for a breachloader, you are more interested in the groove diameter than the bore diameter.)

[tmont]

I had the same experience with a tight bore original Maynard. I was shooting a bullet sized to 518 and getting pretty inconsistent results. Ran a bullet down the bore which measured about 510, so changed to a 513 sizer and started getting much tighter groups.
Tom Montgomery 14th MS

[RaiderANV]

I know from many many moons of playing with Maynards that the bores runs .513 - .517 Guessing as the cutters wore the bore got ah lil' tighter? Then I went back and checked 12 of my originals and found they actually ranged from .510-517 Guess it's possible they started with cutters giving a .508 and wearing out to .518 where they tossed them and used a new set. One can only guess this late in the game.