- 7" for bullets heavier than 70gr.
- 8" for bullets heavier than 70gr.
- 8"* Ratchet rifled 4 groove
- 9" for bullets up to 70gr.
- 12: for bullets up to 63gr.
- 14" for bullets up to 55gr.
- 14"* Ratchet rifled 4 groove
- 15"* for bullets up to 55gr. driven 4,100 pfs or more
- 16:* for bullets up to 55gr. driven 4,300 fps or more
I have been able to stabilize 75 gr. Amax bullets in my 1:9" twist 20" barrel. It really depends on the gun and the load. You should be able to get up to 80 grain bullets to stabilize with 1:8 twist. The only way to really find out with your gun is to test some heavy bullets and find out the limits of your setup. Good luck.
Sierra say their 80gr HPBT Matchkings are for 7-8" twist. Then they say the 90gr HPBT are for 6.5" twist. So Ii guess between 80 and 90 would be your max. Also says the 80 gr Matchkings should be loaded very long. They won't fit in a mag and have to be inserted one at a time. If your on a AR it's a big deal like, but not so much on a bolt. I have a box of Sierra 80gr I need to get rid of btw.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pacomdiver</div><div class="ubbcode-body">how heavy of a 223 bullet can i throw with a 1-8 twist? </div></div>
Hey if your shooting less than 200 yards and need a cheap sight in or plink round. Try PMC 55gr FMJ-BT. I've sighted my AR witha 24" 1-8" twist in with them and they are extremely accurate around that range. I shot a 100 yard that was two staggered and the third almost in the same hole. If I remember correctly around $8 a box, not military crimped and hold up decent.
Stick with the 75 and 77 grain bullets. The 80s were originally intended for the 600 yard line in HP matches for those using AR15s that were loaded singularly (during slow prone) and seated beyond mag limilations.
Unless you long throat the the .223 chamber so you can seat the bullet further out, you will gain little advantage.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rth1800</div><div class="ubbcode-body">I use 77 grain SMK in an 8 twist AR and it stablizes well to 600 yards. </div></div>
What powder and primers are you using. I have a 1-8" AR looking to start reloading a lot. I have 80gr SHPBT but don't want to have to handload them. I looked at AMAX's but I kinda want to stick with Sierra.
I am using Win cases, Russian primers, (Wolf) and 23.9 grs Ramshot TAC with the 77 SMK seated to mag function length. I had one AR that did not shoot this load well. but it was generally very pickey and went down the road.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: couesnut</div><div class="ubbcode-body">has anyone gotten 1-7 to shoot 55's. Just order a new barrel 1-7 to shoot 80 amax but still want to shoot some 55's.</div></div>
I have 1-8" and bought some rem 45gr HP just to have the brass because they were on sale dirt cheap. At 100 yards they either didn't hit the target or was all over the place. 55gr is my lowest.
Your 1 in 8 barrel will handle up to the Berger 82 with no temp or altitude problems. They must be single loaded though. The next jump in .223 bullet weight is the 90 gr. bullets, your barrel will not shoot them well. It should shoot all of the lighter bullets very well.