08-02-2011, 12:21 AM
I gave it one more try. If for no other reason than to get some cases to measure, I tried to shoot my CSS barrel one more time. Cases sized on the short side will chamber, but are hard to extract. Loaded rounds, no matter the OAL, will stick in the lands. When I am able to extract them, there are rifling marks all the way back to the case mouth.
I measured the relative length after firing (protrusion of the case head from a Wilson case headspace gauge) of one round and compared it to several cases fired from an actual Grendel chamber. If my sample of one can be trusted, the chamber of the CSS is about .0045" shorter than the Grendel chamber.
I haven't yet decided exactly how to go about reaming the chamber. My first thought is to remove the barrel and use an empty case to keep track of cutting progress, measuring its protrusion from the breech.
My second thought is to leave it assembled, cut a couple turns, fire and measure the cases. I believe this is the method someone else here used on their CSS barrel. But I'd have to keep making sure the bore and chamber are absolutely clear of steel shavings. Right now I'm leaning toward the first method.
I have cut barrel chambers before. But not for an AR. I don't see how it would be any different, though.
Any thoughts or advice before I get started? Except "take it to a 'smith", or "send it back to CSS". I already have the reamer, so I'm not willing to pay a local gunsmith. And, from what I've read on here, CSS will just say that there's nothing wrong with my chamber and send it back.
Thanks,
Will
I measured the relative length after firing (protrusion of the case head from a Wilson case headspace gauge) of one round and compared it to several cases fired from an actual Grendel chamber. If my sample of one can be trusted, the chamber of the CSS is about .0045" shorter than the Grendel chamber.
I haven't yet decided exactly how to go about reaming the chamber. My first thought is to remove the barrel and use an empty case to keep track of cutting progress, measuring its protrusion from the breech.
My second thought is to leave it assembled, cut a couple turns, fire and measure the cases. I believe this is the method someone else here used on their CSS barrel. But I'd have to keep making sure the bore and chamber are absolutely clear of steel shavings. Right now I'm leaning toward the first method.
I have cut barrel chambers before. But not for an AR. I don't see how it would be any different, though.
Any thoughts or advice before I get started? Except "take it to a 'smith", or "send it back to CSS". I already have the reamer, so I'm not willing to pay a local gunsmith. And, from what I've read on here, CSS will just say that there's nothing wrong with my chamber and send it back.
Thanks,
Will