22-250AI or 22 creed

[benchracer]

That sure seems like a huge gain in case that size, are you sure about those numbers?

Most 22-250AI are generally between 46.3 and 48gr of water. Gaining 7.8gr water more case capacity is a significant increase in just about any case, let alone a case the size of the 22-250. I'm not trying to call you out but something just isn't adding up here, unless you have a very oversized chamber. Heck, a regular 6.5 Creedmoor only holds about 53.5gr water and thats with a 6.5 diameter neck.

Parshal is comparing 22 Creedmoor and STANDARD 22-250 brass (unfired), not formed AI. I believe this accounts for most of the difference.

 

[benchracer]

Benchracer, how does being able to fire 22-250 loads in the Creedmoor undermine any credibility? I'm a little lost on that one.

Undermine credibility? Not making that claim. Undermine your argument? Yes! If you put 22-250 ammo in a 22 Creedmoor chamber, fire it, and out pops formed Creedmoor brass... OR You place 22-250 ammo in an AI chamber, fire it, and out pops formed AI brass, there is NO WAY that the end product is going to be materially different in function or performance.

If the Creed and AI can both be formed in the same way, from the same brass, they are going to be equivalent in volume and performance.

 

[parshal]

Just to be clear, I've not argued anything good/bad/ugly about the 22 Creed vs other 22's. I have no experience with any others. I've just supplied my data that others can use make decisions and arguments. LOL

 

[benchracer]

In the essence of clarity, here are the loads I've personally measured over the Magnetospeed. I have no idea what the deal is with the huge velocity gain with the 80 grain ELD-M. I've not tested any more since I have so many of the Bergers.

77 Grain
R26 39 Sierra TMK 2851
4831SC 45 Sierra TMK 3320
MRP 45 Sierra TMK 3545

80 Grain
R26 48 ELD-M 3650
R26 49 ELD-M 3750

82 Grain
4831SC 45.5 Berger LR 3517
R26 45.5 Berger LR 3540
MRP 45 Berger LR 3400
MRP 46 Berger LR 3515 (good 100 horrible 200 yards)

I don't see your results with the 80 ELD/R26 as being out of line. RL-26 seems to develop initial pressure slowly, then the velocity gains become evident once sufficient pressure builds. I'm not really sure where the dividing line is, but I have seen that mag primers sometimes help in developing initial pressure.

 

[benchracer]

Just to be clear, I've not argued anything good/bad/ugly about the 22 Creed vs other 22's. I have no experience with any others. I've just supplied my data that others can use make decisions and arguments. LOL

Fair enough...

 

[parshal]

I don't see your results with the 80 ELD/R26 as being out of line.

They are 100 fps faster than the 82 grain Berger. Obviously they have different bearing lengths but I've not spent any time trying to figure out why. The 80's were just real fast, surprisingly so.

 

[benchracer]

They are 100 fps faster than the 82 grain Berger. Obviously they have different bearing lengths but I've not spent any time trying to figure out why. The 80's were just real fast, surprisingly so.

It wouldn't surprise me to learn that the ELD has a longer bearing surface than the Berger. That seems to be the norm for the two brands. I am thinking that a longer bearing surface (within limits) could play a role in getting R26 to pressure up. Not sure if I am making sense? Trying to think of a better way to phrase things and failing...

 

[parshal]

I get what you're saying.

 

[86alaskan]

I get what you're after. Kinda like putting a hard crimp on a 454 over H110 so that it has a chance to build before pushing out the bullet. So the ELD has more surface, more initial resistance, thus more starting pressure. Probably helps the burn.

 

[benchracer]

I get what you're after. Kinda like putting a hard crimp on a 454 over H110 so that it has a chance to build before pushing out the bullet. So the ELD has more surface, more initial resistance, thus more starting pressure. Probably helps the burn.

THAT's what I was trying to say! You did a much better job. Thank you!!

 

[venatic]

When you fire a 22-250 round in a 22 Creedmoor not only is shoulder blown out but also the case walls as well..... so it's like an ackley ackleyed.
I have friends with fast twist 22-250AI's and they like them but they run 100 fps or so slower with all else being equal to the 22CM. Now my friends with 22/243AI and 22/6mm can get a tad more than the 22CM if they push'em.

 

[Creedmoor shooter]

Not calling anyone out, but I'm having a very hard time believing a 22 creed is 100 fps faster than a 22-250 AI. The AI has the edge with capacity. It doesn't make sense that the 22 creed would out run it. I think you'd find that If you ran both to full tilt that the 22-250 AI would be a tad faster. As big of a fan as I am of the creed case design, I'm not gonna say something that simply isn't true.

 

[desertcj]

Doesn't sound like or look like a 22-250 Will headspace correctly in a 22 Creedmore chamber? Obviously, the gun goes bang but the picture posted earlier even looks like the case has the start of head separation. Stretching in the web...

 

[parshal]

That's one shot with a light load. There's no stretching there.