I haven't had a 6mmRem since a 600 Mohawk back in the middle 70's. I want to build a prairie dog rifle. My question is: Will a 1in8 twist shoot the lighter(55gr,65gr) varmint bullets at the published valoscities without blowing up?
For the last 20yrs. or so I have concentrated on 22's and 25's. I know nothing more than what I read about the 6mm. I would appreciate any information especially from the gunsmiths on this forum.
Thanks
GOOD LUCK and GOOD SHOOTING!!!

I could tell you exactly what you will get with a 1:8 twist or I can tell you the truth; no one can tell you that!

There are sound ballistic reasons the factory first produced the 6mm in a 1:12 twist - it works great with common for caliber varmint weight bullets they expected it to be use for. A 1:8 6mm should do very well with 105+ grain game bullets but it's likley excessively fast for good accuracy with varminting bullets.

If your question is simply will some very light bullets lose their structural integrity due to the extra rpm's, then the answer is probably "yes" with certain ones of rather fragile construction. Others, like the 55 Ballistic Tip, will probably stand pretty high rpm's (although I haven't put them to this exact test).

You must have a reason for wishing to use a 1-8" barrel when a 1-10 or even 1-12 would probably do better for varmint-weight bullets in this caliber. Want to share it with us?

quote:

Originally posted by Stonecreek:
.....
You must have a reason for wishing to use a 1-8" barrel when a 1-10 or even 1-12 would probably do better for varmint-weight bullets in this caliber. Want to share it with us?

???Ditto???

243 with a 1:12 for 55 to 75 grain bullets

If you are building a dedicated prairie dog -Why not use the proper barrel twist for the bullets you intend to shoot?

You might run into pressure problems before you run into integrity problems in a 243 with lighter bullets...you would just have to see...

I shoot 55-58 gr Nosler and Hornady bullets in my 1-10 Sav HB 243 and haven't had any problems with the bullets staying together...as far velocity wize as I normally go...I shoot for accuracy rather than speed.

I'm working on a 1-8 6-284 right now using 95, 105 and 107 without any problems with 70 gr Speers pushed up there a bit.

The only rifle I've ever experienced bullet blowing up in the air was with my 1-12 22-243 Midd with most 50 gr bullets EXCEPT the old Nosler solid base bullets...but my latest 1-10 22-243 hasn't had any problems with any modern brand of bullet I've used...but I haven't tried the SX's.

What twist is always argumentative and depends on many factors that have to be considered...bullet LENGTH being primarily, accuracy expectations, case size, use, having the disease of "magnumitis" , barrel life expectancy, shooting distance and so forth.

55-70 gr can be screamers but the velo drops off fairly quickly out past 300 yds and the wind play tricks, so going to a heavier bullet balances things out sometimes and also gives you more energy out there...I usually opt for something above 70 gr when I go "longranger" so my 1-10 243 works well with 80-105gr...it's .5MOA or better with Horn, Berger, and Nosler up to ~1.1" bullet length, roughly 75-100 gr bullet weight.

My 1-8 6-284 will be a dedicated 400 plus yd shooter so I will probably use the 95 Sierra MK or Berger bullet...nice balance between weight and velocity.

The best bullet I found for my 1-12 6mm Rem 40 years ago was the 70 gr Speer...it did bugholers in basically a hunting rifle...nothing fancy, just a good tuneup and bedding and prepped ammo.

I had a few favorite hillsides that overlooked ground squirrel villages and I could lob a few in up to ~800 yds...

Don't know if I hit many, it was too far and steep to hike down, then back up...but one would disappear under the ground or dirt cloud now and then.

It would crack you up when you got close and kicked up the dust...the little ratz couldn't put the sound of the shot with the bullet hitting together and they would just run around then set up again looking around wondering "what the heck" and you got another shot.

For general use with bullets from 55-100gr I would use a 1-10...light bullets only 1-12, and heavy bullets 1-6.5 to 1-8.

It's a crap shoot for sure.

Luck

quote:

Originally posted by the jigger:
I haven't had a 6mmRem since a 600 Mohawk back in the middle 70's. I want to build a prairie dog rifle. My question is: Will a 1in8 twist shoot the lighter(55gr,65gr) varmint bullets at the published valoscities without blowing up?
For the last 20yrs. or so I have concentrated on 22's and 25's. I know nothing more than what I read about the 6mm. I would appreciate any information especially from the gunsmiths on this forum.
Thanks
GOOD LUCK and GOOD SHOOTING!!!

Just one question are you using 1/8 twist barrel for the VLD bullets?

Bullet manufacturers' technical reps may be able to help you with your question.

I haven't built the rifle. My 22's are 1 in 12 and my 25's are 1 in 10. I have no experience with "fast twist" barrels. I asked this question to help me determine what I want to do.
Currently I'm using a 25/06 with 100gr NBTs or 100gr SMKs for long range PDs. The 1 in 8 6mm with 105's or 107's intrigues me; however I would also like to shoot lighter bullets for the intermediate distances. I gather from what you gentlemen are saying(asking) that a compromise (say 1in10) is in order and give up on the longer bullets. Thanks for your responses.
GOOD LUCK and GOOD SHOOTING!!!

Just remember if you chamber your rifle for the VLDs you will never get the lighter bullets close to the rifling. You need to decide on what you want before charging ahead. Why not continue with the 25 for the 100-120 grain bullets and a 12 twist 6mm for varmint size bullets.
Butch

If you want the very best accuracy up to 300 yards just use the same twist and bullets used by the bench rest shooters with the 6PPC - (1-14 I think) If you want a little heavier and longer range go to 1-12. In any event there is no reason to go faster than 1-10 for prairies dogs.

The standard 6mm Rem factory twist is 1-9.