ALLEN PRECISION Teaser...

[Rocky Mountain]

Fiftydriver when you did your case volume testing of your 338s using ball powder did you fill them to the top of the case mouth or to the shoulder neck junction?

[Franklin]

Originally Posted by Rocky Mountain

Fiftydriver when you did your case volume testing of your 338s using ball powder did you fill them to the top of the case mouth or to the shoulder neck junction?

Quote from his first post.

I used Hodgdon BL-C(2) powder, filled the cases full to the case mouth and find the case capacity for each.

[HARPERC]

I hope the results are as exciting as the post. I've read it through a couple of times buy did not find an answer. When you state the .300 Allen Express will drive a 200 grain Accubond 3400 fps in conventional length barrels-is 26 inches "conventional"? Thanks for the teaser.

[Camshaft]

From what I have seen on this site conventional is 28"-32".

[Rocky Mountain]

Originally Posted by 300saum

Quote from his first post.

I used Hodgdon BL-C(2) powder, filled the cases full to the case mouth and find the case capacity for each.

I did the same with my 338-416 imp and came up with 52.5gr Ball powder(jamison 416 perant cases)
kerby is hoping for 53grs (Ball powder case volume) in his 338 Excalibur Kerby imp I carn't see how he is going to get any improvement than I'm already getting 3050-3120fps depending on powder and barrel length used????
I'm using N570 and jamison 416 brass, 300 SMK and getting good case life at 3090fps, US869 will easily get 3100fps + with same good case life, this barrel is 30 inches long.

[Long Time Long Ranger]

Rocky Mtn, The Excalibur case is slightly bigger than the 416 case we have been doing for years. I am not doubting you just wondering how you improved it to get the case capacity. Kirby said he cut the angle back and that could have decreased powder capacity back down to the 416 imp. Without seeing both designs I don't know so just asking.

[Rocky Mountain]

Originally Posted by Long Time Long Ranger

Rocky Mtn, The Excalibur case is slightly bigger than the 416 case we have been doing for years. I am not doubting you just wondering how you improved it to get the case capacity. Kirby said he cut the angle back and that could have decreased powder capacity back down to the 416 imp. Without seeing both designs I don't know so just asking.

I am unsure of the case measurements of the 338 Excalibur and was just interested in comparing its extra volume to my 338-416 imp and was shocked to find the same case volume Kirby was talking about for his new 338 Excalibur so that is why I asked the question. Dose anyone know the base, shoulder and length measurements of the 338 Excalibur?
One sight on the internet said you can make 338 Excalibur case from a 338-378 ?? which doesn't sound any bigger than what I've already got, dose anyone now the truth be interesting to know.
It is possible that I have measured my case to the wrong height with ball powder as I just filled the case, hopefuly someone can put some light on all this gray area