GM .54cal 1:70 twist?

[madc0w2000]

I am looking at replacing my .50cal 1:48 28" barrel with a .54cal barrel. I see on Track of the Wolf, that I can get a .54cal 1:70 32" barrel that will fit my Cabelas Hawkins. My question is, what is your opion of a 1:70 twist barrel? I know that it will be strickly PRB, but do you think that is a very slow twist or would it make my PRB even more accurate then a 1:60 twist??

Thanks for your help.....

 

[jtmattison]

The slower 1:70 twist will give you superior roundball accuracy. Not to say it is better than 1:60. It's a matter of finding the right load for your rifle.
I believe there were original rifles made with twists in the 1:100 to 1:110 range.
Generally, the slower the better for roundball.
I also believe the slower the twist, the better your ability to use potent powder charges say 100-120 grains with greater accuracy.

HD

 

[Ohio Joe]

I for one am completely sold on the GMB's 1 in 70 twist for patched round ball. My barrels are 36 inches long and they like anything from a 70 to 90 grain load of 2fg Goex, and they are accurate!

IMHO I don't think you can go wrong with a .54 w/ 1 in 70 twist. :thumbsup:

 

[madc0w2000]

Thanks guys!!! I should have gotten a .54cal when I bought it, but read somewhere that .50cal balls, etc. were more abundent then .54cal. I am using this BP for hunting, so I figure if I can't hit the damn critter with the ball, the extra 4" on the barrel will give me a lot better swing when I charge the critter in hand to hand combat!! :grin:

 

[bart_anastasi]

Do not rule out the conical though.

I have been shooting a 1-66 TC barrel in my 54 cal renegade and a 425 gr maxi ball I cast myself from 80 to 120 gr 2f GOEX lube with Bore Butter.

At close ranges 100 yards is shoots great no tumble.

Give it a try.

 

[shootemup]

You will love that GM barrel with the 1:70 twist. 80 grains of powder under a .015 patched .530 roundball and you'll print cloverleaf patterns all day long.

Spot

 

[pulaski]

Madcow
You will find that the slower the twist the larger sweet spot in the best load .
I have two slower twist barrels (72 & 90)
They have large sweetspots . 8 grain difference in powder same size groups .
IMHO you will love it.

 

[BrownBear]

Interesting! I worked really hard to get a conical to shoot out of my Lyman GPR 54 (1:66 as I recall), and the best I was able to manage was 4-6" at 50 yards. That was with any conical over 300 grains using any combo of lubes and both with and without felt wads underneath.

What lube were you using, and did you use a felt wad?

It shoots very well with PRB however, with any charge from 35 to 100 grains.

 

[WV_Hillbilly]

Contrary to what I had believed for many years in the past... a ballistician friend of mine showed me how a round ball needs almost no twist at all to have decent stabilization in flight. It would have been stupid to argue with him as he had the facts, figures, and data to prove it. Even let me shoot a gun with an extremely slow twist to see it for myself.

You should have no problems at all with PRB ammo.

Regards,
WV_Hillbilly

 

[Wes/Tex]

I believe the point he was probably trying to make would be that of the Forsyth type rifling which was 1-104". October Country uses the Forsyth rifling in their big bore guns. The .62 takes up to 200 grins of FFg, just for an example.

 

I have one for my rifle. The original barrel was a .50 with a 1in48 twist and it did shoot well for the 20 years I had it. I replaced it 2 years ago with the new 1in70 .54 and there has been a noticable decrease in flyers. And I like a looser ball/patch combo. I use a .015 patched .526 RB

 

[haroldpotter]

Excuse me for asking. What does GM stand for?......harold

 

[stalkerhawk]

GM stands for Green mountain barrel company

 

[dave63]

Highly recommended. I have one and I've retired the original barrel.

Dave

 

[bart_anastasi]

Shooting a 425grain Maxi ball from a mold I bought back in 197 somethin or other.

At 110 and 120 gr 2f goex for the long shots 100 yds 70 to 80 grains for shorter distance and to take care of my sholder. Tried 110 grains of 3F once and will not do that ever again.

Just fill the groves with straight Bore Butter now

Back then used Maxi Lube a oil based grease worked great but what a mess.

The big problem if any with the maxi when I load it is to make sure the skirt of the bullets base loads straight and does not dent or misshape.

I now grease and load my maxi into a Quick-shot to help me hold the bullet more firmly upright to load the bullet straighter.

Tried 1/4 inch felt pads dipped in 1/2 Crisco 1/2 Bore Butter but saw no difference in groups.

Loaned some of my bullets to a fella in the local club who was trying to get away from Mini's but he was so used to bullets that drop down the bore when he saw the amount of lead was in the Maxi's front bearing band which is supposed to grave the rifling he did not shoot them melted then down for some other bulet he casts.

Total waste of lead.