Henry Rifle Forums

Went down to the range to try and figure out why my .44 Carbine shoots the way it does with my mild 240 gr. MB bullets loaded over 9 gr. Unique.
Brought along my Ruger 44 Mag SBH too for some comparison if there was any and came home confused with the Henry again.

First up was my Ruger with the 240 gr. MB bullet load with 9 gr. Unique and it shot okay from 25 yds one hand shooting. Then I shot same load
8 shots of it thru the Henry Carbine. Again the shots were to the left but with a couple of nice groups but with one keyhole hit which I think was the first shot.
Next I loaded the Ruger with the hot Underwood 240 gr. JHP ammo and they are HOT! Fired 5 from 25 yds. one handed and that was a handful enough!
Result kind of a spread and my pinky finger was hurting since I place it right under the butt of the grip.
Then fired same Underwood load thru the Henry with a slightly centered spread high of center but no keyhole hits.

I then fired another 7 rounds of the previous 240 gr MB cast bullet load and aimed lower. The result was to the left again with some consistent groupings but 2 keyhole hits this time. The upper keyhole was first shot and the second one was in the middle of the 7 shot sequence.

If instability of bullet causes a keyhole why do the others tend to form a nice group? Move the rear sight over to get on center and you have some good hits with a couple of keyholes....good or bad?
I recently had slugged the Henry barrel and it measures at .431 The MB coated cast bullets measure .4305 and the Hornady JHP bullets are .430 diameter. No keyhole has been seen shooting the JHP bullets. My MB 240 bullet load speed has been checked at 1300-1320 FPS

So would a 1 in 20 twist .429 to .430 barrel be a solution? Mine has the 1 in 36 or 38 twist.

Rewritten because I read the twist rate incorrectly: Yes I would go with a shorter twist rate.

Sir Henry wrote: ↑

Mon Sep 20, 2021 3:39 pm

Rewritten because I read the twist rate incorrectly: Yes I would go with a shorter twist rate.

What I don't understand is if the cast bullets are unstable why do they tend to group together when not a tumble?
If one of the cast bullets measured .430 instead of .4305 would a half thousandth small result in tumble? I haven't measured every bullet.
And why do they tend to got to the left? Might try it again with the ballistic gel and catch a tumbler going thru the gel !

Well forty, we're both having a firearm that shoots to the left with some cast bullets. I think in my case, with the Pietta, it has something to do with the smaller Navy grip. Still a work in progress. As to yours shooting left with those occasional tumblers, that is perplexing. As mentioned, could be the twist. Hmm.

Isn’t a keyhole caused by the bullet not being balanced? Maybe they are not uniform in density.

My 2 cents here. As far as group placement (left, right, up or down), that is strictly dependent on the bullet and powder charge. Once you figure out where the group is, for a particular load, adjust sights accordingly. And group position for the same load, will be different out of different guns.

Now for the rounds that tumble, I think that bullet configuration (MB 240 gr.) doesn't like your barrel and twist rate. No matter how fast or slow you push that bullet, 1 in 5, or 1 in 8, or 1 in whatever are going to tumble and fly from the group. I think you should either try a different bullet of go with the faster twist rate (1 in 20").

Paul

The 430 cast bullets most likely not getting a good bite of the rifling either being just a touch under bore size.

As Paul mentions, I wouldn't expect such wildly different loads to shoot to the same POI, either in elevation or windage. As he says, just adjust the sights as needed.

As for the keyhole issue, you could be right on the edge of stability with that MB load. I'd try upping the diameter just a bit and see what happens.

Lastly, going back and forth between hot jacketed loads and cast loads without allowing for a few shots for the bore to season for either can also produce erratic results for the first few shots with the new load. Have seen it many times. Might try shooting a longer string with the cast load.

And, as always, I've been hesitant to draw too many conclusions from a single range session. For sure, I'd head out for some more testing.

By the way, love the Ruger. It's an old favorite of mine.

Penn Bullets offers 44 bullets from .429 to .432 and now they come coated. Will give them a call and see what a 431 or 432 bullet will do....sample pack! Thanks for the opinions!

Hey Forty, For the last 3 years, I have been shooting Bear Tooth 250 gr hard cast, .432 dia., gas checked bullets through my .44 Mag BBB. Quite accurate with no tumblers/keyholers. These bullets feed perfectly with no severe leading. I use 18 grs. of AA #9 and get around 1650 fps velocity.
Only problem is the 3 - 4 month wait from order to delivery date from Bear Tooth.