When I was working on my 9mm 1911 project I knew I might need to do a lot of test-shooting, so I got some inexpensive cast 125gr. bullets. These were from Aardvark and are sold at Pinto’s Guns in Renton. I’ve shot a lot of Aardvark’s cast bullets, and their 200gr. LRN-FP bullets has been my go-to bullet for .45 practice ammo for many years. I’ve also had great luck with their offerings for .38 Special.
I loaded them pretty conservatively and they key-holed all over the place. I’m sure most of you know this, but that means the bullets didn’t stabilize, exhibited poor accuracy and hit the target sideways. At the time I attributed it to the gun, thinking that the muzzle-blast was interfering with the bullet as it passed into the fixed weight. I mean these were bullets from a trusted manufacturer. It couldn’t be the bullets…
Except it was. When I switched to jacketed ammo the problem stopped. I mentioned this to Chris at Pinto’s Guns and moved on, figuring I’d pass the bullets along to a friend to melt down and re-cast. Then Chris asked me to try to figure out why this was happening so they could determine if they needed to find another supplier for cast bullets. OK, testing stuff is a large part of what I do. Happy to oblige.
First things first- measure the bullets. They all came out to a uniform .356″ in diameter, which is fine. Almost all of the bullets fell within a few percent of 124 gr. Nothing really there. OAL varied with weight, but again nothing stood out. I checked the hardness casually- I don’t have a Brinell test machine- and they seemed kind of soft but not too soft. Puzzling.
The I critically examined the bullet design itself. hello, what’s this?
Only 38% of the bullet’s length actually engages the rifling, and with the bullets not being hard-cast this could be what we professionals call ‘a clue.’ If driven too fast there might not be sufficient engagement with the bullet, and it might smear in the rifling and not spin fast enough. Time to test this theory.
I loaded some of these bullets to 1000fps., 1050-1075 fps. and 1100 fps. and test-fired them from my Sig P-6 and Beretta Model 1951. I didn’t get the photos of these targets for technical reasons (technically I’m an idiot) so you’ll have to take my word for it. At 1000 fps. the bullets performed fine, but sometimes would not cycle my Sig P-6. At 1050-1075 fps. a very small percentage of bullets key-holed. At 1100 fps. more than 50% key-holed. I had thought I would shoot some into gel and examine the bullets, but since it was pretty obvious the problem was velocity-related I didn’t bother.
I also loaded some in ,38 Special that would exit my Detective Special at around 800 fps. At seven yards I was scattering my shots so key-holing would be obvious.
The bullets worked very nicely from the .38. OK, these are now .38 Special range bullets. Not a bad thing.
So the bullets aren’t bad, they are just the wrong bullet design/hardness combination to use in a 9mm. They need to be harder or Aardvark needs to use a bullet that has more rifling engagement. I’ll be reporting the results to Chris and to Aardvark and they can do as they please.
Far and away the worst part of this was all the time and bullets I wasted blaming the problem on the gun’s novel configuration instead of the bullets, but what is life but a learning experience? Mystery solved and I have a couple-few hundred .38 Special bullets. It’s a tragedy of limited scope.
Next time I’ll make sure I am using the right bullets for the job.
Stay safe and take care,
Michael Tinker Pearce, 8 February 2022
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