Author Topic: Question about Contender Carbine rifling twist - (Read 464 times)

AeroE · « **on:** November 05, 2003, 05:21:15 PM »

The twist in my TC barrel in .223 Remington measures 1 turn in 13.625 inches. I only measured it once, and the patch felt tight enough to eliminate slippage.

Does this rifling twist sound par for this TC barrel?

So far it shoots 40 grain VMAX's over H322 great, 55 grain Sierra HPBT's and 50 grain BK's show promise, but 60 grain VMAX's aren't looking so hot - what's the opinion here about maximum bullet weight for this barrel?

[The Greenhill formula predicts borderline performance for all 3 of heaviest bullets here.]

Oldoperator · « **Reply #1 on:** November 05, 2003, 06:05:01 PM »

I believe that the 60 to 70 gains will need a 1 in 11" twist rate. The older barrels come with a 1 in 13" twist rate, but "some" new rifles like the Remington 700 PSS in 223 have a 1 in 11" twist rate. If you want to shoot the heavy bullets you will need the tighter twist rate. The lighter 40 to 55 grain bullets will shoot just fine in your 1 in 13" rifling. I also have a 223 Contender with a 1 in 13 twist that doesn't shoot well with the heavy bullets, but I also have the Remington 700 PSS with a 1 in 13" twist that can shoot the 60 to 70 grain bullets very well.

Larry Gibson · « **Reply #2 on:** November 06, 2003, 09:34:42 AM »

AeroE

"The twist in my TC barrel in .223 Remington measures 1 turn in 13.625 inches."

Your measurement is essentually correct as they are supposed to have a 1-14 inch twist. Mine also has the same twist and will shoot 55 gr FB bullets (and lighter) very accurately with several loads shooting MOA or less. It will not shoot M193 with it's 55 gr FMJBT or anything heavier. Nor will any .223 with a 1-14 twist. Years ago when I got it I assumed it was a 1-12 twist as that was the norm back then. I got it for shooting M193 ammo and it does ok if the temperature is 80 degrees+, not so good below. As I've said it is a very good shooter with 55 gr SXs or the Speer 52 gr HP. I will gladly trade it straight across for a 30-30 carbine barrel if anyone is interested.

Larry Gibson

AeroE · « **Reply #3 on:** November 06, 2003, 04:19:47 PM »

LMG
Thanks, that's the answer I'm looking for. I have a lot of experience with .223 Remington in 9 to 7 twist barrels, but I was extremely surprised to find a barrel with this extraordinarily slow twist for this cartridge. I expected to measure a 12 twist in this barrel.

The 55gr Sierra GameKing shoots slightly better than the 50 gr BK - the BK is quite a bit longer, hence that result should be expected, and of course the 60 grain VMAX is even longer.

The first time I shot this rifle I used 55 gr Federal "plinking" ammo, and the rifle threw shots all over the target - it was so bad that I thought I would have to trade the rifle off, I couldn't even begin to see how load work up was going to fix the mess!. However, free floating the forearm and handloads cured the accuracy problem, now I just have to be consigned to shooting tiny bullets - which ain't necessarily a bad thing.