Home Forums Reloading Varmint Rifles 223ai, 9 twist and 75gr pills...

Thoughts? I am having a Rem 700 with a 24" med-heavy barrel rechambered by Lee (Redneck) as we speak. I hope to shoot 75gr Amaxes or Bergers, but wanted to see what the Campfire consensus was on this. I am in Houston, so at sea level.

Why a 9" if the 75's are your goal? Maybe, maybe not.

7" or 8" is where it's at....

8 twist...just in case....

Yeah, I know the 7 or 8 would be better, but the factory bbl is 1:9. If they don't work, I'll try stepping down. Eventually it'll get a faster twist tube but didn't want to spring for one yet.

My rem 700 tactical shoots 75 amax just fine last time i tried them.

If 75s don't work, you might try some 70 grain Berger VLDs. They work in a 9 twist, work at SAAMI length so no magazine mod is necessary, and the additional velocity offered over a 75 makes up pretty well for the slightly lower BC, until ranges are really stretched.

The weight means slightly more than nothing, other than bullet identification. Length is what is important to be stabilized. The 75gr Amax is notably longer than the 77gr SMK for example.

Here is a link you give you an idea. If you don't know lengths, use the link on the left, then input your specifics; go conservative on the velocity to be honest about it.
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

TXRam,

Aside from the specific bullet that will stabilize in a given twist rate not being dependent on the twist rate, even the people who devise twist programs admit they don't predict everything.

One thing apparent from the JBM program and the one on the Berger site (which are based on the same calculations) is muzzle velocity doesn't have nearly as much effect on stabilization as many people used to believe. As an example, I've owned a .22/6mm with a 1-8 twist Brux that didn't shoot a 75 A-Max nearly as well as .223 WSSM with a 1-9 twist Lilja, when the bullet was loaded to the same velocity in both rifles--and both rifles exhibited the same level of accuracy with other bullets.

A lot still depends on chamber, throat, bore and other stuff specific to the individual rifle.

In the past month I have experimented with two different 1:9 twist AR-15 and 75 Hornady HPBTs as well as 77 Sierras. Both shot well in my particular rifles. An alternative bullet could be 69 Tipped Sierra Match Kings (TMK) if you particular barrel didn't like 75/77 grain bullets.

Just food for thought...

I had Lee do a set back and rechamber to .223AI on a Win 70 with a 1-9" twist last year. It will shoot the 75 Amax into tiny groups one day and 4" groups the next. I'm at sea level or so and it gets really humid here. The 75 hpbt shoots great though and doesn't give up much.

I also find the 75 grain BTHP to be more accurate in my fast twist 22.250s and 223s...

I have a couple of bolt action 223s with the one in 9 twist...
they shoot any 75 or 80 grain bullet I have fed them, from Hornady, Sierra and Nosler....just fine...

My 1-9 Shilen would not shoot the 75g A max or the 75g Hornady BTHP, 223 AI

I tried shooting 75 Amaxes through a Remington with a 1 in 9 twist that was punched out to AI.

I could have literally shot a better 100 yard group with a recurve bow with no sights!

Me too one handed.

John, you lost me here. The first sentence addresses the relationship (or lack of) between stability and velocity. The example seems to address accuracy, vs twist.

I recently tried some 75 AMAX ( thanks to colodog )in a 1-9 Kimber Montana. It didn't like them at all.

I might just try the HPBT one day, in the mean time it loves 40 BT's at 3790.

Thanks all! Sounds like borderline and dependent on the individual rifle, which I figured was the case. I will try 'em and see what happens. If they don't work, will move down the list to the next best couple of bullets. I bought the rifle mainly to play with at the range, no other real purpose so it'll still suit its purpose just fine.

Did it shoot them well before you punched it out?

Had it shipped straight to Redneck from the Seller. Was told it shot fairly accurately.

I assume it's a distributor special as not listed on Rem's website (700 Tactical with 24" med varmint, fluted bbl with 5-R rifling, Cerakoted in a B&C M40 style stock and factory trigger replaced with a Timney - http://www.impactguns.com/remington...-graphite-black-finish-bell-carlson.aspx). Should have the potential of being an accurate rifle, but, if not, for the price it was a fair deal for the stock, action and trigger.

My Remington shoots 75's great, but 55's into small tiny ragged holes....
You'll enjoy it I think.