Figured you guys would like this one. This is one of my Raptor XP-100s chambered in the monster 338 Allen Xpress which is an improved version of the 338 Lapua.
To chamber this class of chambering in an XP-100, there really needs to be some heavy modifications made to the factory XP-100. The XP is an amazingly strong receiver but its stock and bedding sytem are pathetically weak. As such, if you build an XP into a large handcannon chambered for something like the 338 Allen Xpress with conventional bedding, your just asking for failure.
First thing you will notice is the odd barrel contour. This is the original APS Raptor dual recoil lug barrel contour which is currently only retained in the Raptor XP-100. As you can see there is a forward recoil lug held to the barrel with a special threaded NUT similiar to what you see with the Savage rifles. This forward recoil lug supports most of the recoil energy as the rear recoil lug that also serves as the trigger hanger has very small contact with the stock from a recoil support point of view.
Not only is the front recoil lug a nessesity for long term functionality, we also need to support that recoil lug with something other then stock fill material. There is a custom machined 1" square Stainless steel block embeddd into the stock just behind the front recoil lug. The bottom of this block is machined with a round stub that extends through the underside of the stock and appears to be a conventional pillar. A 1/4x28tpi mounting bolt is used through this block and mounts into a drilled and tapped hole in the under side of the barrel to securely hold it into the bedding.
The rear mounting screw is also modified to use another 1/4x 28 tpi mounting bolt which is dramatically larger then the small factory screw. So the Raptor XP-100 uses three 1/4"x28 mounting bolts instead of one 1/4" x 28 and one screw that is about the same size as some scope rail base screws!!!
The bedding of the receiver and barrel starts just ahead of the bolt handle notch and extends with full support up to the forward recoil lug which makes it several times larger in support area then the factory bedding.
SO what else is done to this big handcannon? The receiver is fitted with one of my Raptor side mounted bolt stop levers. This makes things a bit tricker to get a fired case to eject, especially one as long as the 338 Allen Xpress but its doable with some slight work on the ejection port to lengthen it by 75 thou or so.
The receiver is also modified to use the 5, 8-40 mounting bolts of the NEAR heavy duty rail base so its about as stout as possible.
How about recoil, well, with a clean muzzle, the 338 AX would be BRUTAL. Realize that this HANDGUN will drive the 300 gr SMK to 2650 fps with top end loads. When you realize that the Hodgdon load data for the 338 Lapua lists a top velocity of 2677 fps with the same bullet........
Yes, thats a Nightforce NXS in the four NF tactical scope rings. And yes, you can shoot this monster with nearly full field of view without getting your forhead tapped by the scope. I tend to shoot with a very relaxed hold on these handcannons so I always shoot with a 3/4 full view through the scope but I have shot with 100% full field of view with a solid hold and never had any fear of the scope getting friendly with me.
The big 5 port Painkiller muzzle brake
takes care of all your recoil fears. In fact, recovery from recoil is good enough that I could spot my own shots at the test range at 1052 yards.
So what kind of accuracy do these big handcannons produce. Well. It shot a few three shot groups at 1052 yards that were under 3/4 moa and one group was easily 1/2 moa.
Yes this is a specialty handcannon but figured you guys might be interested just to see it. Not to many of them out there but they are truely special. Shooting them is comparable to the 50 BMG or 408 CT based wildcats in experience. It is an event!!!