Gain Twist Barrel

[Randy]

According to Ned Roberts, the gain twist was used for the reasons outlined above by Zonie. The advantage was you could increase the powder charge to increase velocity without stripping over the rifeling. Thus the gain twist was mostly used for long distance target shooting with heavy charges in guns shooting slug bullets instead of round balls. H.M. Pope liked the gain twist too. Why isn't it used much today? I don't know, maybe it just didn't prove to be an advantage. Some cartridge gun shooters still prefer gain twist. They often start at 1:60 or 1:48 and end at 1:20 or 1:15. Fast spin to stabilize a bullet over a long distance was the theory.

 

[fho]

Harry Pope used gain twist rifling. He also tappered reamed his barrels, one end was bigger than the other. Which end was the muzzle, the big end or the small end?

The reason that gain twist is not used much is because it is harder to cut (make). You have to cut it right the first time, you can not lap gain twist like you can uniform twist. It will burn the powder more efficient as the rifling has more resistance than uniform twist. If both barrels,uniform or gain twist, are cut right, one will shoot as good as the other. :m2c:

 

[BLAHMAN]

Harry Pope used gain twist rifling. He also tappered reamed his barrels, one end was bigger than the other. Which end was the muzzle, the big end or the small end?

Do you need a special measuring device to determine that? Something like a 'tape-er measure'? :haha:

I have no idea, but I'll bet that the smaller end was used as the muzzle. I'm guessing that the ball, when shot, would pass through the barrel, create more pressure to escape the barrel and thus create more force applied to the ball. Does that sound right?

 

[fho]

You were 50% right. The big end is the muzzle end. The grooves would not be as deep on the big end, thus the groove diameter would be smaller than at the small end of the barrel. The grooves would be deeper on the small end as the rifling head would be held tighter than on the big end. This would give you a tapered groove from the breech to the muzzle. Now what you have to is reverse the taper of the lands with a barrel lap. You lap the lands at the breech end of the barrel bigger and then taper lap the lands toward the muzzle. In my opinion this is how Harry Pope did his barrels.
Olie :imo: :m2c:

 

[BLAHMAN]

So if I'm 50% right, does that mean I only get 1/2 a star on my test paper? :haha: :haha:

But really now, does that help accuracy? I bet it would. I wonder how did Pope figure this out? I wonder if that happened by chance, ya know, like some good things do.

I can just imagine it now: Pope getting frustrated with the latest apprentice who just screwed up another barrel by daydreaming of something else and not paying attention to what he was doing!

Pope: "Dag-nabbit!! That's the last time I let that pea brained moron run the reaming machine! Oh fizzle sticks! I guess I'll rifle a few of them back assward tapered barrels to see what happens!"

Then he rifles the barrel, fusses around with it and VIOLA, it shoots!!!! History in the making!

Hey, waite one minute, don't we know a guy who......naw, can't be......there is a guy Olie and I know who sets up tapered barrels in his rifling machine backwards! The wide end has the gain in it and the narrow end is the breech. Maybe he's on to something!!!!!!

Olie, do ya think them barrels that 'feller' makes backwards would shoot any better if the gain twist was reversed????

Would that be like a black powder conserving rifle sorta thing? Is them barrels an idea of 'lead conservation'? Can we make bumper stickers that claim "Save the Lead!"?

And the final question is does that reverse gain twist to less twist barrel when fired go MOOB, instead of BOOM? If ya shoot that thing next to a field fulla cows, do they they respond?

So little time.....so many questions.......