9MM with lyman 90 grn boolit

[wildwes]

I've been casting the lyman 90 grn boolits for a beretta 92fs, and I realize these are really intended more for a 380, but I enjoy using them in the 9mm. I can load them and get them to feed and cycle just fine, but I haven't been able to get an accurate load. I size them 356, and I know maybe sizing them a thousandth or so bigger might help, but I cant seem to get decent accuracy from them. I have problems getting the base to fill out nice and square on the boolits, but even when I load the nice square ones they're all over the paper. I've used 5 grns of green dot, which was the best load so far, but still not good, and a couple of loads with Bullseye and Unique, both of which were terrible, the ones with bullseye tumbled. Also tried Winchester action pistol, it didnt do so good either.
So, I was just wondering if any of y'all have any recommendations for a load for this boolit in 9mm luger that you have had success with.

[SierraWhiskeyMC]

Have you scrubbed the bore spotlessly clean to remove any copper/lead fouling, and slugged it to see what diameter boolit your barrel actually needs?

What alloy are you using to cast with?

Tumbling/keyholing boolits with the Bullseye might mean your boolits are undersized, too light, not hard enough, and/or moving too slowly to stabilize.

But first, clean the bore and slug it using soft lead & lubricant. Tap it through using a hardwood dowel or length of brass rod so you don't damage the bore/chamber.

[GabbyM]

92's are known to have big bores. As do most European 9mm's. Regardless if it's made in USA. The tumbling bullet is the big tip off here. You need a larger diameter bullet diameter.

[wiljen]

9mm is one of the tougher handgun cartridges to get to shoot well with cast. The combination of higher pressure than some, smaller powder capacity than most, and finicky guns has given the 9 a reputation for being a bit difficult. Sierra is on the right track, slug the bore and try using .357 or even .358 bullets if they will chamber. My BHP is .3562 but shoots best with .358 for whatever reason. Also, try air cooled and water quenched wheel weights and see which shoots better, sometimes the 9s need water quenched or some other hard alloy to do their best.

[wildwes]

Well, I did slug it a little while back, it was between .355 and .356. It shoots very well with the lyman 120 grn truncated cone, and with some sigmon 125 grn roundnoses that were bought a long time ago. I load both of them to about 1100fps with green dot, unique, and winchester action pistol. I'd have to look at my load notebook, but I think I was loading the 90 grainers to around 1100-1150 fps. I was wondering if maybe this was too fast. The bullets only tumbled with bullseye, I dont remember what the velocity was on that load.
Also, another couple of things I forgot to mention in the first post, the bullets are cast with WW that has some bar solder added. I use NRA 50/50 lube. This is the same alloy and lube that I use for the TC boolits, and it works great. However, I know that little 90 grn RN has a lot less bearing surface riding the rifling, so maybe I do need a harder alloy and need to size it a little bigger. I may try a few in my .358 die next time I cast some of them. Is the velocity they have ok to stabilize this boolit?

[SierraWhiskeyMC]

Well, you haven't mentioned exactly which Lyman boolit you're using, but if it's the 356242 RN design, there's very little bearing surface; particularly if you aren't getting the lower drive band to fill out. All it would have to do is start stripping a little bit in the rifling, and then you'd have hot gases blowing by wreaking havoc.

The 120gr design - is that mold 356402? If so, it looks like that boolit has about 3x the material in contact with the rifling. 356632(100gr) and 356634(130gr) look like a couple other good TC candidates.

The standard 92FS barrel has a twist of 1:9.8425" (.25M); that's pretty quick. It should stabilize boolits at even pretty low muzzle velocities.

You say you're adding "bar solder" to WW's. If it's 50/50 lead/tin solder, you're probably winding up with pretty soft boolits.

If you water-drop boolits using straight WW's, you'll probably wind up with around 14-15 BHN. Without water dropping straight WW's, you'll wind up with a BHN of around 9. Pure lead is around 5 BHN. Adding Linotype to WW's will make them harder. Let them age for a couple of weeks after water-dropping them to allow them to come up to full hardness.

[wildwes]

I'm not sure what the number on either of the moulds are, I'll check when I get off work for the weekend.
The boolits aren't really hard, but they aren't too soft either, I don't know the exact alloy. Also, the bar solder isn't actually bar solder, it's some type of old needles out of some knitting machines from a textile mill. They have been recast into bars and my grandaddy used them for solder. They are a lot harder than real bar solder, they harden the boolits up really well.
I'm pretty sure the 90 grn RN you mentioned is what I have, my boolit is a 90 grn RN design, and it does have very little bearing surface. I have trouble getting the mould to fill the base out. The boolits that do have square, full bases do slightly better, which I know is to be expected, but even they don't do as well as they should. I'm thinking that maybe the suggestion to size them larger may help. As soon as I get a chance to cast some more I'll try that. I start back to school wednesday though, and work Friday, saturday and sunday until the end of september though, so it'll probably be early october before I can cast again. I'll definitely try it then though.