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Full.Lead.Taco-
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edwardbadgley
I’d be interested in a RD design at about 135 or 140 grain with TL grooves so I could tumble lube or PC. Maybe with a radius on the meplat , or even a round nose design. Looking for a general purpose bullet for the 7.62×40 wt.
I like the way your thinking. I have been using the Lee 150 FN in my AR with no feeding issues. The cartridge is my own wildcat, similar to the 300 BO but with a longer cast friendly neck.
jefferyfloyd
Ozarkspirit
The 309-150 SP GC would be a good start. Just take out the lube groove. I’d buy this in a heartbeat for a 300 bo plinkers. There are zero 309’s in inventory right now.
I’m currently working with the HTC 310-173 FP GC. But, it is one finicky mould with the deep hollow points. And sizing it down to 309 is tough on the top punch and the push through die.
i think weight. Then find the mete-plate that will feed and can be hollow-pointed. The NOE 313-150’s i was testing were lead plus tin for fill out. Have only had this mold for a couple of weeks and have only ran a few trough my AR for function test. They feed fine with the exception of the meta plate edge being nicked during the feeding process on my AR. To feed in the AR without issue i think the meta plate will need to be a little smaller than the 313-150.
SwedeNelson
brettsevert
Well this discussion has been going on for quite some time and i’m ready for a new supersonic mold!
Since there is already a 100 grain HP and an HTC 153 grain, I feel like 120-130 grains will net us the round we’re all looking to create with this group buy.
I’m not a bullet designer by any means, I just took the 247 grain drawing and cropped it in paint to come up with a starting idea. I don’t know what body to nose length ratio is necessary for stabilization so that’s also something to take with a grain of salt in my mock up.
We can adjust the meplat if we want it larger and adjust the nose/body length to achieve our desired weight.
So as cornmastah said earlier, can we agree on a desired weight for this. Also voice anything you would like in the final design.
I have been working hard on finding a good cast bullet that has reliable functionality in an autoloader. Problem in most molds out there is the flat nose impedes function. And the spires when set at an OAL that gives good functionality hits the lands because of the ogive is to blunt.
Might I suggest more of a match profile that lets you get an OAL of a minimum of 2.15 and preferably 2.2 to 2.25. And forget the hollow point.
Out of six molds tested from different companies, other than the 230g Lee, the best function is the HTC 153 SP PB. But the problem is that to have reliable function the bullet must be seated at .2 inside the case, which does not give it enough support. And it tends to suffer setback into the case, even with a crimp.
Now, going this direction means a heavier bullet is necessary, as is a cannelure to keep proper seating during the violent action of a autoloader. A nice general purpose round in a match profile would be in the 208g range. It can be shot reliably at subsonic and supersonic speeds. A boat tail will help with seating and a cannelure(s) will keep it in place. With a OAL at 2.25 they will stay put in the magazine and minimize feeding issues. There is plenty of load data as well.
bryanalder
edwardbadgley
jefferyfloyd
Ozarkspirit
jbpaul
SwedeNelson
mto7464
roberttotin
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