hi guys, I bought a new RKS barrel a couple years ago from one of the Single Shot rifle companies and I finally got around to having it installed and I shot it last fall. I was having trouble getting it to group very good at all so I am going to go through the rifle to figure out why and I thought I would start with the barrel. I know RKS makes great tubes, however in looking at the barrel stub, (luckily that my GS saved) I am not sure how to interpret the markings. I tried to post a pic but it would accept my picture, so the markings are as follows top to bottom, clockwise; ".321 C 16X14 AT2 RKS". I know the .321 is bore diameter, C might be chrome-moly, but i am not sure what the rest of it means. Any help

15x8 AT 27"   15 twist to 8 twist @ 27" barrel  length .243 caliber

27x9AT 30"     27twist to 9 twist@30" barrel length  .258 caliber

The gain twist goes from 16:1 to 14:1 in the last 2 inches of the muzzle.
If you wish to shorten the barrel always remove the length on the chamber side.

Most likely the gain twist starts at 20:1 at the chamber end.

RKS barrels are precession single point cut with 40 cuts per groove ending with a continuous choked taper of .0004" from the chamber to the muzzle which improves accuracy by reducing the potential for gas cutting around the bullet.

C is for Chrome Moly barrel and SS is for Stainless Steel.

.321" is groove-to-groove diameter - not bore diameter.
.312" is bore diameter meaning the grooves are .0045 deep.

200 to 210 grain bullets are best suited for this final twist.

A 200 yard iron sight target shot with the same RKS barrel that you have on a .32 RKS 1885 Winchester Highwall with a 205 grain Paul Jones spitzer.
Impossible to measure a gain twist barrel's twist.
The twist gets tighter and tighter as it goes down the barrel.

Yes Ron says you can cut off the barrel without affecting accuracy - but he also stipulates it has to be at the receiver side - NOT AT THE MUZZLE END in the conversations I have had with him.