New Beast from Allen Precision Shooting!!!

I may have missed it, but how does case capacity compare to the 460 Steyr? Looks like your design is a little longer.

I have not compared the two by actually measuring but the Steyr is significantly less then even the standard 50 BMG because its based on a shortened 50 BMG case with similar case body design other then being necked down. The Maximus is dramatically larger capacity then the 50 BMG. Again, have not done an actual case volume measurement test but just going off standard top end loads for each, its clear the Maximus has a very large capacity advantage.
 
I have not compared the two by actually measuring but the Steyr is significantly less then even the standard 50 BMG because its based on a shortened 50 BMG case with similar case body design other then being necked down. The Maximus is dramatically larger capacity then the 50 BMG. Again, have not done an actual case volume measurement test but just going off standard top end loads for each, its clear the Maximus has a very large capacity advantage.
I have not compared the two by actually measuring but the Steyr is significantly less then even the standard 50 BMG because its based on a shortened 50 BMG case with similar case body design other then being necked down. The Maximus is dramatically larger capacity then the 50 BMG. Again, have not done an actual case volume measurement test but just going off standard top end loads for each, its clear the Maximus has a very large capacity advantage.
That's what I thought.
 
I have not compared the two by actually measuring but the Steyr is significantly less then even the standard 50 BMG because its based on a shortened 50 BMG case with similar case body design other then being necked down. The Maximus is dramatically larger capacity then the 50 BMG. Again, have not done an actual case volume measurement test but just going off standard top end loads for each, its clear the Maximus has a very large capacity advantage.

I believe that the 460 Steyr case capacity is about 250-255 grains. Although I don't know your exact case dimensions I suspect your case will hold be somewhere around 310-315. The important thing is your case easily has over 20-24% more powder volume over the Steyr case. The real issue I see is finding a powder that will give close to a 100 percent fill, burn completely from a 36" or shorter barrel ... and not have overpressure issues.
 
I would think that the Maximus would make a great round for the King of 2 miles. Heavy high bc bullets traveling at over 3000 fps. Kind of surprised that several of your designs are not being used at King of 2 miles.
 
I would think that the Maximus would make a great round for the King of 2 miles. Heavy high bc bullets traveling at over 3000 fps. Kind of surprised that several of your designs are not being used at King of 2 miles.

I'm surprised too that some of Kirby's designs haven't been used either! But until recently the BMG case haven't been embraced by the ELR crowd due to brass flow at the higher pressures needed to get the speed. We also haven't seen too many good high BC bullets in the 458 class until very recently.
 
I believe that the 460 Steyr case capacity is about 250-255 grains. Although I don't know your exact case dimensions I suspect your case will hold be somewhere around 310-315. The important thing is your case easily has over 20-24% more powder volume over the Steyr case. The real issue I see is finding a powder that will give close to a 100 percent fill, burn completely from a 36" or shorter barrel ... and not have overpressure issues.

35" will be the shortest barrel used, most will be 38-40" or even longer. With the 680 gr. Load density with US 869 is in the 92% range i would estimate. With bulkier powders such as rl50 its up in the 95 range and with vv20n29 its 100% right now.

With the new test barrels showing up, we will be testing the 10 twist and working with bullets in the 750-800 grain range. This will also help with load density, espeically how slippery the Hammer target bullets are going down the bore.
 
I'm surprised too that some of Kirby's designs haven't been used either! But until recently the BMG case haven't been embraced by the ELR crowd due to brass flow at the higher pressures needed to get the speed. We also haven't seen too many good high BC bullets in the 458 class until very recently.

These rifle systems are also heavy, bulky and not the easiest to shoot because of more recoil and muzzle blast. The potential is certainly there but as mentioned, we need more r&d in the projos in 458.

20-25 years ago, the best out there was the 338-416 Rigby.

10-12 years ago, best thing out there was the 408 cheytac

Since then the big 338s have blown by that level and the 375s in recent years have taken it to the next level along with the 416 cal rifles.

I believe the 458 is the next step in progression but you need a case big enough to get these big bullets to at least 3000 fps. That pretty much means the bmg case.

We are making great advancements in brass quality. Used to have to use surplus pull down mil spec brass. After a lot of sorting and prepping it made decent brass but you also had an hour into each case to make it BR class quality.

IMI brass for the BMG was always the best but got very hard to find.

However now, with RWS and Lapua bmg brass, we have much higher quality, MUCH STRONGER brass that allows the full potential to shine in this class weapon system.

Do i load my 510 Allen Magnum, 510 Maximus and 458 Maximus to higher pressures then standard 50 BMG loads, certainly, but extraction is perfect, case life (primer pocket tightness) is very long so totally comfortable with the levels i am loading to. Certainly no where near red line pressures. Never do that with any of my wildcat designs.

Believe its better to have a big engine do the work easily then to have a small engine work its tail off to do the same work, even if the small engine is capable. Always been my design theory over the past 15 years.

Why do you not see more guys using my rigs in the extreme range comps, likely because thats not where i promote my products. Always been focused on the big game long range hunting crowd and thats where i made my name more then anywhere else.

Not against comp in any way, just made my space on the hunting market more then anything.

I suspect we will see some pop up here snd there in the not to distant future!!
 
35" will be the shortest barrel used, most will be 38-40" or even longer. With the 680 gr. Load density with US 869 is in the 92% range i would estimate. With bulkier powders such as rl50 its up in the 95 range and with vv20n29 its 100% right now.

With the new test barrels showing up, we will be testing the 10 twist and working with bullets in the 750-800 grain range. This will also help with load density, espeically how slippery the Hammer target bullets are going down the bore.

Agreed!
I should be getting some of Steve's 680's bullets next week. Still waiting on my JGS reamer though.
I"m building on a new single feed Mcbros 50 Bmg action that I already have and a hopefully the Manners stock to put it in will arrive in a few months. My 39" Lilja barrel was ordered a couple weeks ago....
Sounds like we need to talk and compare notes!!
 
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Agreed!
I should be getting some of Steve's 680's bullets next week. Still waiting on my JGS reamer though.
I"m building on a new single feed Mcbros 50 Bmg action that I already have and a hopefully the Manners stock to put it in will arrive in a few months. My 39" Lilja barrel was ordered a couple weeks ago....
Sounds like we need to talk and compare notes!!

What chamber you going with?
 
What chamber you going with?
Actually building two platforms. A tactical 460 Steyr with a 34" barrel and and my own ELR design based off a slightly shortened version of an improved 50BMG. Very similar to yours but with a longer neck and 37 degree shoulder. It will have a little less case capacity than yours though.... Case capacity @ 300 grains
 
Actually building two platforms. A tactical 460 Steyr with a 34" barrel and and my own ELR design based off a slightly shortened version of an improved 50BMG. Very similar to yours but with a longer neck and 37 degree shoulder. It will have a little less case capacity than yours though.... Case capacity @ 300 grains

Steyr for easy shooting, hotrod for serious shooting!!! LOL

I still have a couple 50bmg rifles in the herd, just in case things go real bad, should still be able to come across mil spec BMG.

Thats also one of the few GOOD reasons to own a 308!!
 
35" will be the shortest barrel used, most will be 38-40" or even longer. With the 680 gr. Load density with US 869 is in the 92% range i would estimate. With bulkier powders such as rl50 its up in the 95 range and with vv20n29 its 100% right now.

With the new test barrels showing up, we will be testing the 10 twist and working with bullets in the 750-800 grain range. This will also help with load density, espeically how slippery the Hammer target bullets are going down the bore.

How does the RL50 compare burn rate wise to the 20N29? Does RL50 take more powder to fill the same place up as 20N29?

Thanks Kirby!
 
So just ran some numbers. 680 gr. Bullet, 1.01 bc, traveling at 3150 @ 5000 ft elevation would have over 5000 ft pounds of energy at 3000 yards. Wow!!!!
 
How does the RL50 compare burn rate wise to the 20N29? Does RL50 take more powder to fill the same place up as 20N29?

Thanks Kirby!

The lots I have tested of both show that RL50 is noticeably faster burning then VV20N29. VV20N29 is a very large kernel size, much larger then RL50 so it will displace much more volume for a given powder charge. RL50 is actually a pretty dense for volume stick powder.

Comparing RL50 to H50BMG, some lots seem identical, some slightly faster or slower, just depends on the lots of each being compared, similar though in both burn rate and density. I would say RL50 is slightly more dense then H50BMG.
 

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