Home Forums Hunting & Shooting Custom Rifles & Wildcats 7-08 AI ?????????

Does anyone have one or know something about them?

What kind of velocity could be expected with 140 grains and a 24 " bbl?
Thanks
Steve Eggers

I'm in the act of putting one together; a friend gave me a new take-off barrel from a Rem CDL and it's being reamed out to AI. I will put it on a Rem short action.

I expect to get over 3,000fps with a 24" barrel. I have a 270-308 on the same action (not improved) with a Douglas 22" barrel and I easily get 3040 fps with a 130 grain. It's never shot worth a damn (a 1 1/2" group is a good one) so I'm making the switch.

I think between the extra 2" of barrel and the improving it should do about as well as the 270-308, but the important thing to me is that it shoots well.

I also base this estimate on the fact that I have a 280 improved with a 24" barrel and I can easily get a little over 3200 and brass lasts forever. This about 100 fps faster than my standard 270 which has a 22" barrel.

Good look with yours, and let us know how it shoots; I'll do the same.

jmbn

3000-3100 fps should be REALLY easy. Try IMR 4895

I would say from 2900fps to 3000fps, best I could in a 22.5" and a 23" bbls was 2975fps in two different 7-08AIs.

MtnHtr

I bought a 7-08 VSL with the Idea of reboreing it to AI or 284. After shooting Light Magnums in it I decided not. It shoots the 140gn @3000 chronied in my gun and 1- 1.25" groups. I used to shoot reloads and hunt L/Ms. Now I just use reloads 100fps or so is just not worth the effort to me. my $.02, capt david <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />

You guys are right on with the velocities. I have a 23-1/2" 7-08AI on a Sako action.I've had it doing nearly 3100 with H414 and a 140 Ballistic Tip. It shoots 140 Ballistic Tips over IMR4350 into nice little groups.And if you are in Canada, you can buy it!

http://www.canadiangunnutz.com/viewtopic.php?t=5573

Contact Kenny Jarrett,
This was his original favorite caliber. All his early Beanfield rifles were 7mm-08 Imporved, and he claimed 7mm RemMag velocity was pretty easy. Well, very close, and that was over a decade ago. The Vit 500 series powders and other newer powders should get you well into 7mm Rem Mag velocity range. Just be careful. If your getting the accuracy you like, but not the velocity, you can have a smith give you a little more freebore "ala Weatherby", and step on the gas some. It's all a matter of what you want to achieve. Just be careful.

Safe Hunting
Clint

Southpaw--
You are a little confused on the Jarrett rifles--Kenny's first beanfield rifles were .280 Ackley's, not 7-08 AI...

Ditto on what Jamison posted. I will add that Jarrett did inflate the velocities on the 708AI data he had listed on his website awhile back. It was pretty misleading.........

MtnHtr

Triple dittos on the above posts.

The 7-08 AI has about 8-10% more case capacity than the std 7-08. This is less case capacity than a std 280 or 284. Therefore with equal pressures it will not equal the velocities of the 280 or 284. Expect 2% to (maybe) 3% more speed over the std. case.

7 mag velocities out of a 7-08 AI is not gonna happen and would be a very dangerous goal....... <img src="/ubbthreads/images/graemlins/shocked.gif" alt="" />

JimF

JimF,



Good post, somtimes makes one wonder about those magic velocities! I've worked with two 7-08AIs and could never break the 3000fps safely using 140s. The mid 2900s are about as fast I care to load for and that is probably right at max. MD did an article on the 7-08AI and came away with similiar results I think.



MtnHtr

Thanks for that, MH and Jim--I was amazed he would post those numbers. I don't have a 7mm-08 AI--can you guys really get an xtra 4 grains of powder in an AI over the standard case??? That is all I get out of going from a 280 to a 280 AI.

Maybe I am wrong but if you are shooting for 3100 out of the 7mm-08 case it would seem you are way over pressure wise or your chrongraph is needing a check--i mean imagine what you could do with a plain old 280 and 16 more grains powder capacity...and please don't start going off on some efficiency hokem.

tomK:

There is much stuff posted on the internet about velocities, accuracy (as in....my rifles shoot 1/2" groups all day long), case efficiency and other ballistic magic. Much of this is either stupid hotrodding, and/or just plain BS.

There are posters on this board that are gun industry professionals. They have access to real pressure testing equipment, and they have faaaaaaar more experience than any of us, including hotrodding "experts" These guys have published some interesting information about pressures and velocities.

Some of their conclusions are..........

Velocity increases @ about 1/4 the percentage of case capacity. Ie: if you increase case capacity by say 12% you gain about 3% in velocity.

Conventional pressure signs often don't show up until well past the sammi maximums. Which is usually ~~ 58-63K depending upon the cartridge etc.

There is no ballistic magic in case shape.

Velocity increases/decreases at about 20-25 fps/inch in barrel length.

For several years I was a hotrodder myself. I was fairly young and very impressed by ballistic tables and high velocities. At the time, no cartridge was "Magnum" enough for me. I thought industry figures and loading manual maximums were just for conservative old fuddy duddys. I owned several 7 mags a couple of 300 wbys and assorted other stuff. I loaded them all hot (very hot).

At the time I thought I was a cool dude and a very savvy reloader for beating the book velocities so easily. At this later date, I now realize that I was both uninformed (stupid) and very lucky to not have hurt something (like my face).

JimF.....................(older, smarter, cheerful fuddy duddy.... <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />)

What JimF said. Except for the Fuddy-Duddy part. <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />

NO more hotrodding for me. Book velocities, or book max charge, whatever comes first. If I want more speed, I want a new rifle. Simple as that.



Rick

Ditto on what Jim said. I don't really see the point in "ai-ing" any modern looking cartridge but to each his or her own...

BTW, I've read where the 223 ai gains 200 to 250 fps over the standard 223 but don't see how that's possible with sane pressures... Maybe it's magic....

That would be with a max charge of PD #124......

That's pixie dust #124 (provided by the Tinker Bell powder co.)

I wouldn't do a 223 AI expecting huge velocity increases, but I might do it for other reasons (like case trimming)

JimF

Never tried any pixie dust powder. More of a Hodgdon Extreme powder sort of guy... <img src="/ubbthreads/images/graemlins/cool.gif" alt="" />

You boys really have hurt my feelers.

Might have to build another 223AI to get over the newfound angst..................(grin)

Definitely must compliment JimF on a most sensible post. These days of affordable chronographs I see shooters more hung-up on velocity than ever. When someone mentions a new chambering or wildcat cartridge the first word out of their mouths is: Velocity!

Personally I don't see why everyone is so hung up. I only hunt deer for the most part. I came to the conclusion a long time ago that I don't need a magnum rifle to hunt deer. In actual practice the standard chamberings work just fine. However, I do like the wildcat rounds. Not just for velocity, tho'. As always, I seem to have a hankering for something just alittle bit different. I do use a chrongraph. Because a chrongraph tells one a lot more than just velocity.

I see no valid excuses for trying to make a cartridge do something it is not designed to do. (i.e: hot-rodding). If I need more gun, I just go it to the safe an select a bigger one. <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />

Mostly I just use what I like. The traditional medium bores...the9.3Guy