Home Forums Hunting & Shooting Handguns 10mm 220gr Heavies... Anyone Messed With These?

I'm about ready to start working up loads for the new Ruger GP100 10mm. I have the Lipsey's edition, 5.5" barrel. I have a supply of Rimrock 220gr cast. I'd like to get what I can out of them, Underwood and Buffalo Bore are getting 1200fps. Underwood Pulldowns have yielded 800x and Longshot. Two powders I have on hand are 800x and Blue Dot. Longshot and Power Pistol and AA#9 appear to be the other popular choices for experimentation. I'm not opposed to buying them.

If you have done this, you know about the scarcity of data. Anyone else messed with these? Appreciate any related experience.

So it's completely apples to oranges, but I was just today testing some loads for my 10mm Glock 20. I was using the 200gr Montana Bullet works SWCGC bullets. I tested two charge weights each of HS6, Power Pistol and Blue Dot. The Blue dot loads were the winner in my pistol. One of my best friends (now deceased, damn cancer) swore by AA#9 in his 10mm glock. AA#9 and Blue dot are pretty slow powders - I'd tend to start there if I was you, as opposed to the faster numbers.

With heavies 180 grs. and up I have had great results with No. 9. I would start and end there. Some other powders may get there more efficiently (i.e. take less grains per round) but if you want accuracy, power/speed, and safe pressure in hot 10mm loads No. 9 does it perfectly.

Mark in GA

The burn curve with Longshot would make it a great candidate, and it always produces excellent performance in the 9mm, 9mm+P, 40 S&W, and 40 S&W+P I've tried, particularly with heavyweight bullets. I've had great luck with plated 220's in the 40, shooting them at about 1050 with Longshot. It's a heavy-spring load, for sure, but causes no wear and tear. Until I got a 200gr GCWFN mould, it was my bear load in an XD 5". I'd start with the powders Underwood uses. I doubt you'll get the top speed out of AA#9. It just isn't that energetic compared to Longshot, Power Pistol, Blue Dot, or 800x. You may get better accuracy though, and the push will be a bit gentler. As well, if #9 works, 2400 will also work.

Bad advice Huntnshoot.
Those comments about #9 are not at all accurate. It is pretty much the perfect burn rate and density for maximum velocity in heavy 10mm loads, and will meet or exceed the velocity you can get with any of the other powders mentioned. It's not at all like 2400, which can not generate good velocity in the 10mm because it's too bulky, you just can't get enough in the case.

OP, the Blue Dot you already have will give you pretty good velocity too. I'm not going to offer my load data, since the 220 gr bullets I've worked with are different than Rimrock's and that can have a big effect on pressure. However, I can tell you the biggest differences you'll see between #9 and Blue Dot are flash (lots for Blue Dot, very little for #9) and metering (#9 meters great, Blue Dot is less consistent).

If #9 is the best, why are boutique ammo companies not using it? Hmmmmm....

Appreciate all the advice. As far as pushing the 220's I will likely try 800x first, and if I am not satisfied then I will get some Longshot. If I can verify that Buffalo Bore is using Power Pistol, I'll try that too.

8.6gr Longshot is the way to go with the 220's.

http://10mm-firearms.com/factory-10mm-ammo-pull-downs/underwood-220gr-hard-cast-pull-down/

I would lean towards Longshot for high end loads.

Hey 79S, yeah I saw those posts about the Underwood pulldowns. I believe previously to Longshot they were using 800x.

I'm sure I'll get a can of Longshot and test both

From what I read 800x was prone pressure spikes and doesn’t meter well. So I went with longshot

Yeah, I may grab a pound of Longshot today. Have you messed with the 220's?

Mostly because it uses more powder, meaning it costs more per round. If you're trying to maximize profit, do you load with 8.5gr of Longshot, or 13 gr of #9? That doesn't mean Longshot performs better, it's just more economical.

If you're not familiar with something, it's best to not give advice about it.

That is correct, 800X meters like cornflakes. If you want to run max loads with it, it's best to weigh each charge, because they can vary a lot. Blue Dot is better but still not great. #9 and #7 meter the best, with Longshot and Power Pistol pretty close behind; all four of those meter nicely.

Huntinaz, email Rimrock, they will almost certainly give you some idea as to powder charges.

I've loaded 215 SWC's with Blue Dot, worked well, but I didn't push it too hard; I don't care to share the data.

I wouldn't care to try 800X for that application.

I can't speak to the Accurate powders or Long Shot as I haven't tried them for that heavy a bullet.

I was thinking of emailing Rimrock as well, I think I will.

I picked up a pound of Longshot just now.

Yes I have, running them out of a Glock. But I been looking at the gp100. I found a good supply of good 220gr hardcast. I run longshot out of my 40withn180's I'm getting over 1,000 FPS with it.

Would like to know more about that good supply of 220 hardcast if you are sharing. I've been using some 200's and would like to try the 220's.

This is where I got mine. I believe there's at least one other maker. Xtreme? Zero?

Rimrock 220gr Hardcast