7mm-08-vs-7mm-08AI

[Jim Hundley]

With a 24" barrel,what velocity difference between these two cartriges?Would the AI version be worth the added fireforming,etc.Would a shooter really tell the difference in a hunting situation?
Thanks,
Jimmy

 

[Varmint Hunter]

The 7mm-08 is already a fairly straight walled cartridge and velocity is not greatly improved by doing an AI conversion. Between the fireforming and the potential feeding problems my vote goes to - NO.

Improving the 7mm-08 is like improving the .308; not usually worth while, IMO.

However, wildcatting or just plain ol' improving is not always about practicality. Sometimes it's just for the fun of it. /ubbthreads/images/graemlins/smile.gif

 

[jhead7416]

I have both calibers in 24 inch barrels. The AI is a Douglas premium SS and regular 7-08 is factory matte VLS. While both calibers are great rounds, the Ackley Improved is just plain cool looking with its 40 degree shoulder. I have found over three years of load development that the AI velocities are not significantly greater. But by getting a custom barrel, talented smith to chamber the round, it is more accurate than the regular 7-08. If I had it to do over, I would get a custom barrel in regular caliber.

 

[hvy barrel]

[ QUOTE ]
I have both calibers in 24 inch barrels. The AI is a Douglas premium SS and regular 7-08 is factory matte VLS. While both calibers are great rounds, the Ackley Improved is just plain cool looking with its 40 degree shoulder. I have found over three years of load development that the AI velocities are not significantly greater. But by getting a custom barrel, talented smith to chamber the round, it is more accurate than the regular 7-08. If I had it to do over, I would get a custom barrel in regular caliber.

[/ QUOTE ]
I agree with jhead7416 I don't think that the gain would be worth the fireforimg trouble. Your money would probably be better spent on a new Hart, Shilen, or other brand barrel. Then have it installed by a competent smith.

 

[SamSpade]

A better option would be to make the 7-08 into a 284 Winchester.

 

[NZVarminter]

I've been looking at the 284, but even the 7mm08 has to seat bullets into the case in a short action with 140g bullets. The 284 is a longer case so the bullets end up seating even deeper into the case so you must loose quite a bit of the extra capaicty if you stick to an OAL of 2.8

 

[wapiti13]

NZVarminter, I built my first 284 on a "short" action that required a 2.800 OAL. 140 gr bullets were easily pushed in the 2800-2900 fps range. My second rifle was built with a longer magazine box and other modifications to allow an OAL of 2.950. Now a 140 gr bullet will easily go 2900-3000 fps. An improvement over both 7/08s and great accuracy with the 284 case. Both rifles had 22" barrels. FYI. /ubbthreads/images/graemlins/smile.gif

 

[TOM H]

You can get a Wyatt extended magazine from Brownells for the Rem short action so the 284 will work. I have one up the gunsmith now being finished. My first wildcat was a 7x57AI years ago, I got almost 7mag velocity with bullets up to 160gr using 10gr of powder less. Another choice would be the rem short mag case in 7mm or the wsm case give you plenty of velocity with either and not have to fireform cases, sure want to use the Wyatt magazine box and have them throated out long to get alittle more case capacity with those cases. Only reason I'm talking about different cases is I got a 7mm Kreiger barrel coming and I'm looking for a caliber. I think the 7-08 is a good case left alone, I use to shoot a shorten 7-08 think that improved that case alittle got better velocity than the standard 7-08. I was shooting a short 308 back then so making cases for either wasn't a big deal.

 

[NZVarminter]

Waipity13

So just what sort of mods can you do to the Remm 700 to extend the OAL to 2.95.

I had a quick look at the feed ramp last night and cant see that you can move it foward much as the front face is really the metal that the bolt lug transfers its load to.

The most you could do would be to steepen up the ramp so it starts at 2.90 ish. But my 243 dosnt really feed that well as it is so if it was any steeper it must put a lot of lateral load on the bullet as it feeds. Kind of defeats the purpose of going to all that trouble with competition seater and making sure there is minimal runout, then have a steep feed ramp that potentially pushed the bullet out if alignment.

 

[wapiti13]

NZVarminter, See my reply under your other inquiry about the 284 in a SA Rem. Good luck.

 

[NZVarminter]

Found it, thanks, just what I wanted to know.

Cheers

Grant