Just ran the "cleaning rod measure" and it's between 8 and 9". So I'm guessing it's not 1/7. I've loaded a bunch of different 55, 69 and 77 gr loads. Off to the range tomorrow.
Just ran the "cleaning rod measure" and it's between 8 and 9". So I'm guessing it's not 1/7. I've loaded a bunch of different 55, 69 and 77 gr loads. Off to the range tomorrow.
It’s 1:9 then because 1:8 was never offered in 223. (As far as I know.) And yes, the 77’s are about on the ragged edge. If the 69’s shot so good, you might simply stay with them.
FWIW, my favorite load in the 22" barrel axis (1-9) was 23.5gn of Varget with the 77gn SMK (2805fps). It gave me consistent groups at 600yd less than MOA, even in a little wind. The Hornady 75gn ELDM was almost as good with the same powder charge, but, when seated out it was too long for the magazine.
I have a Savage LRPV 7 Twist in 223, some 50 and 55g handloads will make it 100yds to the target, others don't, about 1 out 4-5 don't make it. Loves the 68/69g ammo. My barrel is stamped 7T IIRC.
I went back to the range today with a number of different 55 gr loads. None shot well. Both the 69 and 77 grain loads shot very well
Hey Dave... I am looking at a used Model 12 .223 stainless bull barrel with bull fluted barrel.... did these have 1/9s or 1/8s back then? I have a Remington Varmint from that era and it is a 1/12. I would be thrilled if it is a faster twist. The reported accuracy of that other one would seem to indicate this... mine looks to be a 2002.. THANKS ... I need to tell them in the next hour if I want it. The store put a brief hold on it for me. Thanks Mike
Either 1:7 or 1:9 twist. The 1:8 was never offered for the 10/110 series or affiliates, in 223 Rem. 1:8 was only offered on the Savage MSR (AR15) starting in 2018 & with a 223 Wylde chamber.Originally Posted by tigermikel
Edit: If your rifle is 2002, it is 1:9 Twist. The 1:7 wasn’t available in the 10/110 for 223 Rem until 2007.
BTW... I am an old Philly kid- Lafayette Hill. Returned to Philly for grad school at Penn. So thanks! Mike L
No kidding? You’s from dis same jawn… like me? How ‘bout dat.
Just so you won't think a 1:9 twist limits you to 69 and 70 grain bullets.
My 1:9 marked barrels on my 12 FV and on my CZ 527 both measure out slightly faster than 1:9 twist. As best I can tell with the cleaning rod technique, my 12 FV is about 8.75 or so.
(Dave and other machinists on this forum can attest better than I to how difficult it might be to get a barrel twist precisely to 1:9.)
I tend to believe that the twist rating is a guarantee that the twist is a "not slower than rating" rather than a guarantee that it is precisely right on the rated twist.
Much to my surprise, my 12 FV shoots 77 grain SMKs and TMKs and Nosler CCs and Berger bullets among the best of all the bullet weights.
I then tried 77s with my old (7000 round) CZ 527 1:9 twist and it shot the 77 gr SMKs as well as any other bullet it has ever shot over the years.
My 12 FV shoots 73 gr ELD-Ms better than any other bullet.
It also shoots 68 gr Hornady Match bullets incredibly badly - the worst of any bullets I have ever tried - to a 3x larger group average than 69 grain SMKs, TMKs, and Nosler CCs.
None of that seems to make any sense based upon conventional beliefs.
From my limited knowledge, I believe that performance in any barrel depends on the bullet shape as well as the weight.
The only way for you to figure out what your barrel prefers is to shoot bullets 'down the tube'.
I would recommend that you shoot a lot more than 1 group before you make any decision.
Posting Permissions
Reply With Quote
Bookmarks