7mm08 rem 1-9 twist ?

Highpoint

Full Member
Full Member
Minuteman
Feb 19, 2011
288
0
40
Cullman, Alabama
Im putting together a savage simi custom build with a 1-9 twist 26" long, 1" at at the muzzle Criterion barrel. My plan was to load 162 gr a-max over varget powder. I now have just seen the twist recommendations is 1-7 to 1-8 after buying.

Anyone having success with a 1-9 twist with the 162 gr Hornady A-Max. Thanks for the replies.
 
Re: 7mm08 rem 1-9 twist ?

I'm running a 1-9 1/4" Twist in my 7mm-08, and 162 A-Max's work just fine.

If your really concerned, run this calculation:

JBM Stability Calculator

For example a 162 grain A-Max @ 2700 FPS in a 1-9" twist barrel yields a stability factor of 1.606. Stability values should be in the range of 1.3 to 2.0 to ensure bullet stability. So 1.606 factor would be more than fine.
 
Re: 7mm08 rem 1-9 twist ?

In most cases a 1-9 twist will handle up to 180gr. bullets. It's what I'm running in my .284 win.

The 7mm-08 and the 160gr. bullet weight you should be just fine. If memory serves me right at 2600fps (if you can get that with 180's in a 7mm-08) you need something like a 8.7 or 8.8 twist min. to stabilize the 180's.

If your gun doesn't shoot any of the 160's check the twist of your Criterion barrel. It's made by button rifling. The button could slip and the twist might not be uniform.

Other than that you should be good to go.

Later, Frank
Bartlein Barrels
 
Re: 7mm08 rem 1-9 twist ?

I ran 1-9 on my 708 with 162's in a krieger 26" tube, stable all the way. Mine were running in the 2600 to 2700fps range and were very accurate,even had some 1/4 moa groups. You should be fine.
 
Re: 7mm08 rem 1-9 twist ?

Savage factory 7mm twist is 9.5 and I've been told the 162 Hornady and 175 SMK work great in a factory Savage barrel, so 9 twist should be more than sufficient.

You should also be good with the Berger 180 VLD with that 9 twist, though it *may* be velocity dependent.
 
Re: 7mm08 rem 1-9 twist ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: craigp40</div><div class="ubbcode-body">You're fine. Don't sweat it.
However, look at H4350 as your powder. It's likely you will hit pressure too soon with Varget. I did. </div></div>

+1 Try IMR8208 also...
 
Re: 7mm08 rem 1-9 twist ?

Currently I load 308 win, 223 rem, 243 win, 7mm-08 rem (a browning a bolt), 30-06 spr, 22-250 rem all with varget with very good accuracy and very acceptable fps. I currently stock this powder on the shelf in 8# cans and was going to try it first. I have the hornady # 8 manual and IMR 8208XBR is not in the load data. I did buy a can to try in 223 rem and 308 win when it first hit shelfs and I had very good results but varget was just as good, so the 1/2 can has been collecting dust. What are you using for a 1/2 power load and if varget strikes out I will burn the rest of this can?

Mscott, how many grains of h4350 are you using for 2800 fps , as Im thinking thats a little to risky to be shooting here in the HOT Alabama summer?

Thanks for all the replies and even though Im still a month out on recieving my barrel, load development is starting right now !!
 
Re: 7mm08 rem 1-9 twist ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mscott</div><div class="ubbcode-body">My factory 24" 9 twist handles 162s very well. I'm using H4350 and getting 2,800 fps. </div></div>

Same here, Except mine's a 8.7 twist. 9 works great thou as all the others have stated.

The H4350 did the trick, I played with all the regulars including RE17 (primer pockets go to shit) and 8208 (low speeds) and settled on 45.5 (cold) / 49.2(hot) for my loads. The big difference is jumping the bullet (the amax doesn't care in my rifle anyway)

When I seated them into the rifling. I got pressure befor I got to 2700fps. But with a .050 jump. 2800fps is still quite easy and I've gone as high as 2861 but its hard on the brass.

This should go without saying (DO NOT DUPLICATE THIS LOAD) Work up on your own. (even though it under Hodgdon's book max
 
Re: 7mm08 rem 1-9 twist ?

My 18" 7-08 sends 162AMAXs just fine through my silencer. I use RL15 and get 2700. That being said I have the round seated all the way out in an AICS mag with the front plate removed.
 
Re: 7mm08 rem 1-9 twist ?

I'm currently running a 26" barrel with a 1 in 8 twist. My competition load is as follows.

162g Hornady BTHP (w/amp jacket)
47.2g H4350
2.870 OAL
CCI 200
Winchestor brass
2775fps

For under 700 and also good for hunting I would probably go A-max

162g A-max
47.2g H4350
2.904 OAL
CCI 200
Winchestor brass
2700fps

The A-max loses stability past 1000yards for me and the BTHP holds stability at to atleast 1250 (as far as I've tested to date). Both rounds are .02 off the lands on my barrel, and the Ogive on the BTHP is much different.

Good Luck,
Merritt
 
Re: 7mm08 rem 1-9 twist ?

Those out there that tried varget, did you have the muzzle velocity recorded at max charge, and would you mind sharing your results? I did some ladder test rounds for accuracy at 37,37.5,38,38.5,39,39.5,and 40 grains . I am going to go with accuracy but so far with all my other long range paper punchers thats been at max charge or close to it.
 
Re: 7mm08 rem 1-9 twist ?

Pressure with Varget and 162 AMAX started for me at around 40gr (2574fps). Group size was ok, SD in the teens. Blew primers out at 42gr (2705fps). Had to stop shooting so no numbers on group size or SD.