APS Big Boy!


Jun 18, 2007
NE Wyoming
APS (Kirby Allen) Big Boy!

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Ernie quit that. Your going to make me have to have one if you keep it up. I still haven't matched your Prairie Dog shot even with a rifle. Every time you stop in the guys that work for me start talking all over again about how they want one of those. If you keep this up I will have to buy one just so they can go shoot it and at least quiet them down for a while.
Shortened Near 20 MOA picatinny base
Modified McMillan stock
Trued Action.
Double recoil lug design (first of its kind)
Lilja 1-10 twist barrel - 338 cal.
It was supposed to be 18", but Lilja made the flutes to long so it is 18.5 (Grr
5-Port Pain Killer Brake-I guess that is a 1/2 more inch velocity:D
Cartridge- 338 Allen Xpress or 338AX (338 Lapua Magnum Improved)
Gunsmith - Kirby Allen / APS

The pic I posted is from Kirby. I actually do not have it, because Kirby wanted to do some accuracy testing before he sent it, but the wind has been howling for the last 2 weeks+

Kirby has done some chronoing with Retumbo (CCI-250 primer) with 225AB's, 250 AB's and 300 grain SMK's. After the chronoing and checking pressures and different MV's he came to the conclusion, that H-1000 would likely be a better powder than Retumbo for the 225 & 250 grain bullets. The AB's have a heavy solid base compared to some other more pressure friendly bullets like the Barnes TSX and Scenar's. Won't know until we try it, but there may be more MV's with different powder/bullet combination.

Here is some MV's for the three different bullets:

225AB - 3076 fps
Comparing this data to the Hodgdon's best load for the 338 Lapua with this bullet weight in a 24" barrel, they list 3040 fps as their top velocity so not to bad besting a 338 Lapua in a rifle length barrel.

250AB - 2890 fps
Hodgdon lists the Lapua at 2850 fps with this bullet in a 24" barrel length so again, we matched or exceeded the standard Lapua in a rifle length barrel.

300SMK - 2720 fps
Hodgdon lists the Lapua at 2670 fps in a 24" barrel length, again, we topped that by a decent amount.
Kirby said that H-1000 may even work good for the 300's, and may get you more velocity but with this bullet weight, but to be very careful and not push things to hard. With a 300 gr bullet, the pressure spike can get very aggressive with faster burn rate powders.

Recoil wise, Kirby said the 225's were warm and fuzzy.
No comment on the 250's, but he said shooting offhand with elbows bent (see through the scope 4.5-14 Leupy) he had to have a little force to make sure it didn't come back on him to much.

We have several SP's based on the Lapua, Lapua Improved or 338-300 Rum Improved (338 Edge).
Eric Wallace (Crow Mag) started things off several years ago with a 18" 338Lapua Imp, and now Doug has a standard 338 Lapua, and Neal has a 338 Edge.

I think Doug's is a 20" and Neal's is a 19" or 20" (Help me out guys, if I am wrong here.
This is giving us an idea of what can be done with some very large bores/capacities.
Steve (sscoyote) is the one who pushed me over the edge to do this, so I guess I can blame this project on him

This will be the first time I have ever owned a SP that would hold from 97.0 - 107 grains of Retumbo with a loaded bullet.
Once I get it I will be putting a Huskemaw scope on it.

If I get an accurate load with the 300's at 2700 fps (4500 ft elevation, 59 degrees, 200 yard zero, 10 mph full value wind):
------------DROP------10mph DRIFT

500 yards - 7.50 MOA ---2 MOA
1000 yds - 24.50MOA ----4.25
1250 yds - 35 MOA -----5.50MOA
1500 yds - 47.25 ------7.25
2000 yds - 79.25 -------10.50 MOA

I really like the looks of it and can't wait to actually get it.
A 225 grain bullet going 3000fps+ from a pistol with a riflescope being warm and fuzzy :cool:
Thanks Ernie and Kirby for turning that ich into a rash :D
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