Post by Deleted on Feb 21, 2015 5:38:52 GMT -8
I love my morning coffee. Sitting at the computer on Saturday morning is truly one of life's simple pleasures.
While perusing through all the web sites I frequent, I find this post about a Savage barrel for sale. Its chambered in a 5.56 based case in .277 caliber, that has been shortened considerably. The seller is claiming 2800 FPS from a 20 inch barrel with a 100 grain bullet. How is this even possible?
I pulled up some data from Western Powder Company for the 6.8 SPC and found that it can't push a 95 grain bullet that fast. Even with a 20% increase in powder the 6.8 can't get it done, and that is running at 58,000 PSI.
Don't get me wrong I love wildcats. Most all of you reading this, know that. But if you are going to build, procure or design a non SAAMI cartridge, don't make some outlandish claim about what it will do or not do. Always error on the side of safety. Pushing a notably smaller case to that kind of speed can only be done 2 ways. That is with an excessively hot load of fast burning powder, creating astronomic pressure or it's all imaginary and the designer is trying to sell something that it really isn't.
I guess what all this boils down to is, if your going to build a wildcat, pressure test it. Work your loads up and test it again. Don't make wild claims. If it's a mid sized cartridge ( for an AR 15 ) then keep it at that. Don't try and sell it as running with the big boys, because it can't. Shoot it and enjoy what you have created. If you want to go faster use a bigger case. Just do it safely.
OK rant over. Enjoy your coffee.