View Full Version : 6.5-06AI or 6.5x284

Pat B.
01-22-2008, 05:15 PM
Does the 6.5-06AI out perform, velocity wise, the 6.5x284 ??

Given the same platform would one be more accurate @ 1000 ?

Are dies available for the 6.5-06AI ?

Thanks for any input,

J. Pendergraft
01-22-2008, 06:41 PM
[Does the 6.5-06AI out perform, velocity wise, the 6.5x284 ?]

The 284 case and the unimproved 06 case are almost identical in capacity so if you improve the 06 case you can get more velocity from the 06 AI than the 284.

[Given the same platform would one be more accurate @ 1000 ? ]

There is nothing inherently more accurate with one vs. the other. Both have performed very well at 1000 yds.

[Are dies available for the 6.5-06AI ?]

You likely will not find a suitable die for the 06 AI without having one custom made.

01-23-2008, 06:54 PM
Watch the best bullet speeds for the slugs you want to send down range.

Many perform their best from 2900 to 3000fps with an 8 twist. Going faster doesn't improve anything. Some research here should pay dividends.

You may find that the 6.5-284 is more then enough case unless you are forced to use shorter barrels.


Charles E
01-23-2008, 08:56 PM
With the 6.5/250 AI, my log book shows a three shot group, extreme spread 3,052-3,055 with a 150-grain custom bullet. Raising the charge got 3,100 to 3,108 (3 again).

With a 140-grain flat-base (long shank), I was getting 3,109-3,113 (again, 3 shots). This load also got small group of the year at Hawks Ridge in 2006, a five-shot 2.445. Actually, this group was a tie, but they gave it to me based on a higher score. The other 2.445 was shot, of all things, by a 6.5/284 -- but I'll bet dollars to donuts the bullets weren't going as fast.

This was with a 8-twist ratchet-rifled barrel. These, and the 5-R profiles seem to get a higher velocity.

You really want a 9-twist barrel for the 6.5/06 AI, & probably for the 6.5/284, at least if you are going to push it. I got that 8-twist RR barrel at a bargin I couldn't pass up.

To answer you question, yes, you can get higher velocity with the 6.5/06 AI, and yes, you can use it to good advantage, but you may have to experiment will bullets. And don't forget, that higher speed is a very marginal factor. Might make you feel better, but on any given day, a 6.4/284 will clean your clock, just as the next day, you'll clean theirs.

If you get a 6.5/05 AI, I'd recommend setting the chamber up to use RWS .270 brass. It is better than the 6.5/284 brass, but costs more. TANSTAAFR

Dave Tooley
01-23-2008, 09:01 PM

I was building 6.5-06 Imp before Lapua made 6.5-284 brass. The reason was better quality brass. The 06 case will get about 150 fps more than the 284 case. Most of the time with equal accuracy.


Correct me if I'm wrong but once you get past about 3150 fps accuracy begins to falls off.


J. Pendergraft
01-23-2008, 09:19 PM


Correct me if I'm wrong but once you get past about 3150 fps accuracy begins to falls off.


With the 142 MK my experience has been somewhere in the 3160-3175 fps range with a 28 in barrel works best. You could get that with an improved 6.5-284 but I don't think you could get there with a standard 6.5-284.

My little experiment a few years back with the drastically shortened 404 case necked to 6.5 would deliver 3400 fps easily however it copper fouled terribly and did not meet my accuracy expectations for 1000 yd benchrest.

01-24-2008, 02:31 PM
I have shot both for the last 4 years at 1000yds. I have found them to be pretty equal. The 06 IMP is faster,( at least 150 more like stated earlier) but they both shoot best from 2950 to 3050 fps (@1000yds 142SMK). I had the 06 IMP up to 3400 with RL22, But I won't go there. I had better luck in competition with the 06 IMP. The 284 has carbon build up problems (for me), which I did not have with the 06 IMP. The 6.5/284 is easier if you are lazy, no case forming. You just buy good brass. I used both 270 Win and Lapua 06 brass, both with a 270 neck bump of .010 for fire forming. Too tight of neck gave me pressure problems on the 06 IMP. You need at .003 to .004. I used Amax 140 , 140 & 142 SMK and 139 Senars, the 142 SMK was the overall best for me. I like the 6.5/06 IMP the best, but it is more work.