What would be the best rate of twist for a 7mm-08 that will never shoot heavier than 140gr bullets? I have a 1-9 already and that would cover any 150-175gr loads so this gun would be strictly 140's. Does 1-10 sound OK?

woods

10 might theoretically do better, but my 9 1/8 or 9 1/4 shot 100gr in 1/2" group 3 shots at 200 yds.

There can OFTEN be too slow a twist, but going too fast, never seems to be so counterproductive as many seem to worry with, so I would be happy with 9, even with 140s, as heck mine did great with 100gr, so you need not worry about 'over' stabilization, not near like 'under' stabilization if you had a twist too slow. I use an 8 twist for 70-105 in my 6br, and would not be afraid to use 55-60gr if I chose to use them.

1:10 would be ok, but there's really no point in paying extra for a non-standard twist.

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What would be the best rate of twist for a 7mm-08 that will never shoot heavier than 140gr bullets

1-10"

I don't believe you can over stabalize a bullet so I would stay w/ the 1-9 or 1-9.5 that most 7mags use.

The Rem standard for 7mm08 is 1-9 1/4 and I shoot in the .2s with 130, 150 and 160 gr bullets. The 100gr will shoot in the .3s so if i have to rebarrel I know what I will stay with.

Thank you for the info, I'm having a pac nor barrel made so the cost to do 1-10 rather than their std 1-9 is nada. I'm more interested if it would improve accuracy.......seems most are happy with the 1-9. I just figured with a 7mm-08 already at 1-9 that would handle the heavier stuff that maybe the 1-10 would be a better starting point for a gun that will never shoot anything heavier than 140's.

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A 10 twist will handle up to and including a 160 gr bullet.
A 12 twist will handle up to and including a 140 gr bullet.
These are minimum twists which is the most conducive to accuracy.

It was this quote from another member that got me considering this change. Would the 1-10 tend to give better accuracy because its more of a minimum?

woods

Don't complicate things. The 1 in 9 will work good with the full line of 7mm bullets. If you hunt anything larger than deer, the 160-175's are perfect in the 7x57 and would be the same in the 7-08. Always it is better to 'overstabilize' the lighter bullets than understabilize the heavies. I am not sure there is such a thing as overstabilizing. Talk to the AR15 guys, the 1 in 8 rifles seem to shoot 50-55 grains as well as the 1 in 12 ones did and shoot the 69-70 grains a hell of a lot better.

You know, I owned an Abolt micro medallion in 708 and it shot with my heavy bbl Rem 700, but I would NOT choose anything other than 9 if spending the money.

Chris/Pac-Nor has built all my custom's save one. UNLESS you are shooting competition with lighter bullets, I doubt you will notice any detriment.

I have shot with factory 9 1/4 like above, 5 shots one hole with 139 and 140's at 100 yds.

They will shoot great. I would be more concerned choosing contour, length, crown, and chamber specs, I ALWAYS do min spec saami, so as not to neck turn, you should be able to use factory ammo if desired, and get great accuracy.

My pac-nor 6BR shot under 1/2 inch at 330 yds, they do good work in my experience, well, actually better than good, and they WILL stand behind their products AND they are a good value, so I expect to use them the next build as well, good choice.

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Don't complicate things. The 1 in 9 will work good with the full line of 7mm bullets. If you hunt anything larger than deer, the 160-175's are perfect in the 7x57 and would be the same in the 7-08. Always it is better to 'overstabilize' the lighter bullets than understabilize the heavies. I am not sure there is such a thing as overstabilizing.

Yeah exactly.

I have had 3 7mm-08's, 1 had a 1-9 twist, the others were both 1-9.5 twists.

All would shoot bullets down to 120's very well indeed, as a matter of fact my last one would shoot 130-150 grain bullets into .5 moa, if I got my shit together.

Like previously said, it is an advantage to be able to shoot heavier bullets under certain circumstances, particularly if some long range shooting is needed. That is where those heavy, high BC bullets come in handy.

I could not get by without being able to shoot the 162 Hornady SST's out of my 7mm-08.

Personally, I think that going to a slower twist with the 7mm-08 is a big step backwards.

You did say "That will NEVER shoot heavier than 140 grain bullets"...1-10 twist

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I just figured with a 7mm-08 already at 1-9 that would handle the heavier stuff that maybe the 1-10 would be a better starting point for a gun that will never shoot anything heavier than 140's.

Yes....I have a pac nor 1-9 twist barrel on a gun that will be used for any heavy bullets. This gun will NEVER be anything but 140gr's.......its always been that way for the last five years with the factory barrel,things won't change. Pac nor acted like it would be the same accuracy with 1-9 or 1-10 with 140's and thats hard for me to believe I guess. Just wanted some opinions from the knowledgeable gang on here.....lotta experience in one spot. Thanks

woods

Never is a long time. Your thought on not heavier than 140's could change, or you may want to sell it to someone who likes heavier bullets. The 1 in 9 just has no disadvantages.

I've built a lot of rifles in this cal & it's one of my all time favorites. Long before Remington hijacke... er uh, commercialized it, we called it the 7mm souper. I've always felt the round was best suited for 150 gr bullets & under and always used 1:10 twist with great success. That said, lots of folks have fine accuracy with the old std 1:9" using lighter bullets too, so, just flip a coin and enjoy a great caliber. Here's my wife with a moose she took with one in AK, using a Nos. Part. 140 gr.
http://hometown.aol.com/brayhaven/myhomepage/huntfish.html

Nice Moose pic! We're lucky enough to have a good population of them here and have been drawn twice so far to hunt them.

Well its just a barrel and at the rate I shoot it will be pretty worn in another five years or so......that coupled with the fact that I NEVER sell any of my favorite hunting rifles makes most worries about resale or changing my mind kinda moot. My other rifle will always be there for any heavier bullet shooting......although I prefer the 140 partitions for even moose hunting. Heavy longer bullets poke too far down into the case and limit powder capacity a little too much for my taste.

All that said if the difference in accuracy is not any real difference, and its really just a flip of the coin afterall. That makes the 1-9 seem a better choice if theres no real advantage to going with the 1-10.

Thanks for all the good info.

woods

I had my 7-08AI barreled with a Shilen 1:11 twist, which is what Shilen recommends for bullets up to 140gr. I believe that 140gr bullets are a perfect match for this cartridge, and I knew I would never be tempted to shoot anything heavier than 140gr bullets in this rifle. If the game I'm hunting requires more thump, I am better served by my 300 Win mag. The 11 twist easily stabilizes 140 gr bullets, is extremely accurate, and gives good velocity. If you have any questions, call Shilen.

What length is the barrel? It seems to me that would make some difference. The 1x9 1/4 works great in my 20" barrel with the 140s.

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I believe that 140gr bullets are a perfect match for this cartridge, and I knew I would never be tempted to shoot anything heavier than 140gr bullets

Then I believe you are wasting alot of the potential of your 7mm-08.

I can launch a 162 grain Hornady SST (BC of .550) from my standard 7mm-08, at above 2800fps.

I recon it would quickly catch up with your 140 grain bullet.

Hi Tumbo, read some shooters on a long range sight were using that amax on long shots on deer, with good effect, I myself having shot a 105amax in 6BR at 2815 with deadly results at 400 yds on a deer, double lunged.

Are you hunting with yours? If so would like to know what powder and/or load yours likes, bbl length, brass used, and if you have any hunting reports. Thanks for any feedback you give.

Hi 6.5BR

Yes I hunt with my 7-08, but never enough. I also occasionally use it for silhouette matches.

I can assure you that the 162 SSt's and the 168 sierra match kings relibly put the rams at 500 meters down with much more authority than any 140 grain bullet will.

I hunt mainly pigs, most are shot inside 100 yards (so no advantage there using the 162 over a 140), occasionally though, I will take a shot at one crossing the plain, out to 400 even 500 yards if I have a good rest, This is where that high BC bullet really shines.

I may also occasionally come across horses, donkey's or scrub bulls that the property owner wants gone and the 162 grainer is definately an advantage there.

My rifle it a Tikka M595 continental with a 23 and two thirds inch barrel(600mm), it will shoot .5 moa all day if i'm good enough.

I use lapua 243 cases with 48 grains of ADI AR 2209(I think is hodgon H4350) behind the 162 SST's or 48.5 grains of reloader 19(compressed)

I have also used the 162 A-max with its BC of .625 but I just couldn't get it to shoot as well as the SST or matchking.

My bad, the SST is a different bullet than the amax, but I am sure if anything, it is a better game bullet. Thanks for the info, great speed in a 23" barrel.

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What length is the barrel?

21" for woods hunting.......seems the debate on twist is argued well on both sides and good points are made by all. The only thing I know for sure is the gun will not see over 140gr bullets and thats a fact. I can't ask for a better bang-flop load than the paritions have been for me at the close woods ranges up here. Just thought maybe there would be a slight increase in accuracy and velocity with the 1-10 over the 1-9.

woods

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Originally posted by woodseye:

quote:

What length is the barrel?

21" for woods hunting.......seems the debate on twist is argued well on both sides and good points are made by all. The only thing I know for sure is the gun will not see over 140gr bullets and thats a fact. I can't ask for a better bang-flop load than the paritions have been for me at the close woods ranges up here. Just thought maybe there would be a slight increase in accuracy and velocity with the 1-10 over the 1-9.

woods

Not sure there was a "debate" Woodseye. From what I read, this caliber works great with all the common twist barrels it's chambered in . Let us know how yours comes out.
BTW: I agree with half your sig line

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I had my 7-08AI barreled with a Shilen 1:11 twist, which is what Shilen recommends for bullets up to 140gr. I believe that 140gr bullets are a perfect match for this cartridge, and I knew I would never be tempted to shoot anything heavier than 140gr bullets in this rifle.

Just another point as someone here compared the 7mm-08 with a 7x57 mm. There is a huge difference, the 7x57 has a longer throat and its CIP twist rate is 1-in-8.66", and as such it is designed to shoot longer and heavier bullets.

In contrast, the 7mm-08 is short-throated and hence bullets of 140 grains are more appropriate to use, and so a 10" twist is more than adequate - here we see that Shilen in fact recommends an 11" twist.

Everything in the 7mm-08 is shorter than for a 7x57 mm, built on a short action with a smaller magazine box to house a shorter case ...

Warrior