Tried some custom made 178gr TNFB bullets this afternoon and had pretty good results. Had got up to 2133 fps when I had to stop. My goal was a power factor of 375 and made that right off the bat which isn't bad for a 16". The 147gr AP loads did as expected. Penetrated block walls with no problem with the core tumbling. Got two chronographs now to make sure I don't screw up the numbers again.
I have been asked about making barrels in this chambering. I wouldn't offer anything unless I know it is absolutely right. There is more to designing a proper functioning system than just having a reamer made and chambering a barrel. A third revision on the reamer may be needed for the M16s and I believe I may do something with the gas port location as it seems just a tad too far forward still.
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