Twist too slow ?

[Double 30]

I have a 2 year old Green Mountain barrel on my T/C Hawken ( flinter) and I'm wondering. Its a .50 cal ball barrel with I believe, a 1-70 twist. Although it might be me , I havent been particularly impressed with its accuracy. So far an average of 2 inches for 3 shots at 50 yards is typical. Given she's peep sighted I think she should do better than that. So far, her best load is a .495 ball .020 patch lubed with either bore butter or crisco and 70 gr of 3f Swiss black. Greenhill's formula gives a 1-66 as optimal for a .490 ball and I wonder if 1-70 is a bit slow.The barrel has 192 round through it so perhaps break in is an issue. Any ideas? Any help appreciated. 

[Josh M.]

Every gun is a rule unto itself...but...

You would have a hard time convincing me that you could tell the difference between the ballistics of a 1:66 bbl and a 1:70 bbl.

Adv 2" at 50 yards sounds pretty good to me - what kind of groups do you get with your other iron sighted guns at 50 yards?

Have you really run out of other variables to tinker with?  I'd be sorting your RB's by weight, trying different lubes, powder charges, patch thickness, and maybe even different powders before trying to change my barrel.

Good luck - JM.

[flintlock]

It's not the twist, I've shot these things since 1975, they are very forgiving...

What do your fired patches look like??? Where are you buying them from???
What are they made of???

[Double 30]

Fired patches look like I could shoot them again.I 've tried bore butter , crisco, maxi lube Shenandoah liquid lube and cleaner. I've tried . 015, .018 and .020 patches , I prefer pillow ticking though. I've tried Goex and Swiss in both 2 and 3f. I swab between shots. I've shot cast and swaged balls of .490 and .495 diameter too. I live close to Dixon's Muzzleloading shop and Chuck believes that 1-70 is ok for a .50. I can shoot an inch or less at 50 yards with my Yugo SKS( that one's in a class by her self...) and my Black Diamond XR. The Yugo has issue sights and the Black diamond wears a peep sight as does the flinter. I know 2 inch groups at 50 will kill a deer deader than a stump, but it seem that she should do better...

[Buckskins & Black Powder]

i wouldnt be happy with that group, i expect that @ 100 yards.  Have you tried a heavy load? my traditions is a powder pig, 110gr 3f goex. My lyman GPR i had was the same way.

[Double 30]

I've gone as high as 80 of 3f Swiss and 90 of 2f Goex. She doesn't like Goex, but the 80 of Swiss did show improvement. She shoots like a smoothbore if I dont swab. I was hoping she'd shoot lighter loads well but maybe she needs the velocity...

[kevthebassman]

My experience with my flinter (a GM .54 barrel 1:70) has led me to believe that these slow twist guns like to be stoked hot.  The hotter I stoke the fire, the more accurate mine gets.  Mine also prefers 3F, 110 grains of Goex 3F to be exact.  With that combo and my good eyes I can shoot a ragged hole at 50 yards.

[quickdtoo]

I'd have to agree with the hotter loads, my GM .50cal flint shoots nice 1-2" 100yd groups with 95gr of 3F under Bore Buttered pillow ticking and a .495" ball for a hunting load. 

Tim

[Double 30]

Took her out today and started with 90 gr of 3f Swiss and a cast .495 ball in bore buttered pillow ticking ( .018) and got a 6 1/2 inch 3 shot group at 50 yards. Dropped back to my usual 70 gr and shot a couple 2 1/2 inchers. Tried some Crisco as patch lube, same size group, and the tried some Shenandoah liquid and actually got ( slightly ) under 2 inches. I'm not the best flinter by a  long shot, but...I tried the 70gr charge with a bore butter patch at 75 yards and got a 6 7/8 inch 3 rounder. frustrating. Will heave a few ( quite a few) more balls before our flintlock season opens on 26 Dec. Hopefully its me and alot of practice will give better results.Otherwise its no more than 50 yards for this one. 

[flintlock]

I'm no fan of bore butter...For 20 years or so, I used SnoSeal...Last year I started using a home made lube that I picked up on over at www.muzzleloadingforum.com
This is a mix of bees wax, castor oil and Murphy's oil soap, it's good stuff and protects better than bore butter...

I'd try putting either hornets nest, a fiber wad or a lubed patch between the powder and patched ball...I'd also load a dry ball and then pull it to check the patches for cutting...My .54 has a 1-72 twist and my normal hunting load is 80grs FFF Goex...But, my barrel has cut, not button rifling that's .015 deep or so...I'm not sure if your's is button (usually .008 deep) or cut...

Anyway, for some reason I get good accuracy with 50-120grs of FFF powder...

[Double 30]

Flintlock, I did dry ball her and no cutting on the patches.However, ther was the prettiest weave imprint on the ball, so all is well there. She seems to do better with a lighter weight lube in cold weather.I have a bunch of .50 cal. sabots that didn't work well in one of my inlines and I think I'll cut the petals off and use the base as an overpowder wad. Honestly though, the patches come out in such a condition that I would reuse them with confidence. Her barrel slugs as follows; bore .500 groove .520. I love the rifle. Balances perfectly, points like my finger and is very pleasant regarding recoil. I'm hoping its just a loose nut behind the buttplate... 

[Double 30]

Just for the heck of it I tried shooting her with unset triggers and lo and behold she tightened up considerably. Perhaps it was the increase in lock time that set triggers cause that exaggerated followthrough issues. By that I mean a single trigger trips the sear directly while set triggers add an additional motion to the equation ie; the set sear trips then the lock sear trips. It adds to the lock time apparently enough to magnify any followthrough issues. I'm getting 3 inch groups at 100 now.Practice will no doubt improve that as well.