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wgr
08-12-2010, 12:13 AM
anyone here ever look into a super slow twist barrel like mabe 1 in 104.

DIRT Farmer
08-12-2010, 11:30 AM
Some of the old round ball bench rest shooters use to use super slow twists and a lot of powder. The slowest I have heard of was 1/ 14 feet and a Dixie cup of powder.

northmn
08-12-2010, 01:30 PM
The English Baker rifle had a 62 bore (some say 64) and a twist of 1-120. It was capable of pretty accurate shooting. Twist rate is also proportional to bore diameter, such that the 1 120 in the Baker would be very slow in a 50 and not so slow in a 12 gauge. There has been a lot of discussion over twist rate with round balls and mostly it has boiled down to a big ado about nothing. About the time someone suggests that a 1-70 performs with heavier charges better than a 1-48, someone else will show an exception. Many twists have been tried and the barrel makers have stayed with the old standards. Saying that I did order a 33 cal barrel with a 1-34 inch twist to make a squirrel rifle out of, hoping it will perform well with a lighter powder charge than the 1-48.

Northmn

Northmn

FL-Flinter
08-12-2010, 01:40 PM
Forsythe ran 1:144 (12 feet) in his .62's, I had .62 with 1:109, just built a Jaeger for a client who supplied his own 1:120 .62 barrel, couple years ago I sent a .40 target rifle out with 1:72 that shoots money making groups with 25gr of 2F.

There's no one right answer to the twist rate question, it all depends on what you're doing and contrary to the myths that so permeate the muzzleloading world, a slow-twist bore does NOT mandate using large powder charges, the quality of the bore and consumables is what matters. If you're not going to check every ball for consistency of mass and balance, expect to have to push them harder to get the RPM required to counter the flaws. If you're a "dumper & rammer" don't get a slow-twist. A "dumper & rammer" is one who just dumps the powder down the bore then rams the ball down by whatever means is necessary. Slow-twist, especially in smaller calibers, require consistency on loading just as they do on the consumables. It doesn't do any good to pick out the best balls then beat them into the muzzle with the butt of your knife. Likewise, it doesn't do any good to carefully load the best balls on top of a powder charge you just dumped into the bore any old way. Loading a muzzleloader should always be done in the same manner as loading for a BPCR in measuring the powder carefully the pouring it slowly and methodically allowing the bore to function as it's own drop tube and topping it off with a quality ball/bullet that is loaded with care and consistency. While the preceding applies to all ML's I do have to note that even though faster twist bores are somewhat less picky about loading inconsistencies, they do have a tighter limit on maximum velocity.