Here are some of the specs on this action I have been working on for about 12 months. The owner of Cor-bon Ammunition funded the project and they will market it. It's being made by a machine shop here in the valley that makes all my other parts. The action in the pics was just sent to HP White Labs and had a pressure test done. They took it to 89,000 psi before the cartridge case went so elastic that it flowed into the ejector slot and firing pin hole, proof loads run about 70,000 psi. They had to beat the bolt open with a dead blow hammer but once open checked the headspace and it had not changed and the NO GO gage would still prevent the bolt from closing. I examined the barreled action when it returned and noticed the Douglas Barrel had swollen .002 at the chamber end as the barrel was difficult to remove. However the action did not expand by any measurable means that i can detect. The lugs did distort but only by .0017. So all this proves is with modern steel and using a proven design you can stay out of harms way. In short these are the highlights.
The originally request was to make an action large enough for the 338 Lapua, 416 Rigby and 450 Rigby as they all derive from the same case then make an action with the rails and magazine for the 300/375 H&H cases and then a magazine for the 300 Wtby, 340 Wtby, 416 Rem and 458 Lott group. The owner decided to go with the 300/375 H&H action, rails & magazine first.
The steel we started with is a Chrome Moly called Flexor, but we have also made some from 4340 C/M. The ID of the action race way is .703 the bolt OD is .698 there is little side to side or up and down bolt wobble when the bolt is fully retracted.
The bolts have been made from the same Material as well as 2 bolts made from 8620. As of yet we have not settled on the final steel for either
It uses a cone breech like the M-70 has a 1.062 x 16 TPI thread form that is housed inside a large ring that measures 1.400 OD and is longer than a M-70 by 1.00 here and there. This give you a bullet ramp as long as a 98 Mag Mauser and a longer thread extension. The threads or cut in with a thread mill and to date have been dead zero with the centerline of the bore. The measurable run out across the recoil lugs seats, recoil lugs, bolt face and receiver face are less than .0003 there is no need to lap anything before fitting a barrel.
Anyhow, very promising action. It's nice to see the industry working hard at improving our gear.
