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Pasco
03-12-2017, 10:53 PM
First post. Hello.

Do subcompact 9mm with 3" barrel make 125 power factor?

The reload data I see for lead round nose bullets show it is mostly at max loads that you get there, and the data is for a 4" barrel.

That's the question, here's the less relevant intro stuff. I reload for my revolvers, rifles and shotguns but am shopping for my first pistol and want to compete. There is a regular IDPA match nearby. I don't know how much that short barrel will cut velocity. I like the feel and utility of the subcompact, but if I can't compete with it I need to broaden my choices.

Last comment, if you want to suggest a load, I'm all ears. Naturally I would want to use Clays or Universal since I have a few cans, I have some Blue Dot as well, but as usually happens when you pick a new round you get a few new powders to try.

Any insight is appreciated.

-John

#IDPA (https://pistol-forum.com/usertag.php?do=list&action=hash&hash=IDPA)

GuanoLoco
03-13-2017, 07:55 AM
I haven't spent much time with shorter barrels. My 134PF competition loads shoot through my Shield just fine but I haven't cronographed them.

I suggest:

Use polymer coated lead bullets.
Get access to a chronograph.
Use a fast modern powder - there are new choices available.
Experiment with light (124 gr), medium (135 gr) and heavy (147 gr bullets) for power factor, reliability and accuracy.
Watch for pressure signs on the primers. I prefer federal primers for this - they are soft enough to actually read signs (for me some flattening is normal). Other harder primers may not show signs until you are well past acceptable pressures.
Don't be afraid to try bullets from a different manufacturer - bullet profile/width can matter.

1986s4
03-13-2017, 09:18 AM
I haven't shot IDPA for a few years [I do miss it] so check this out for yourself. But I think you are allowed to use the longest barrel length allowed in your division to make power factor. So, if your 3" doesn't make it then you are allowed to test in the longer barrel. Almost every match I've been tested in they used a test pistol of the longest allowable length, not my pistol.

Jim Watson
03-13-2017, 09:25 AM
Depends on just how "sub" your subcompact is.
I have read that The Box with BUG spacers is built around the S&W Shield.
So if your choice is no larger than a Shield, it can enter BUG where the power factor is only 95 to accommodate .380s.

If it does not fit the BUG Box, then it must make f125. Look at Ballistics By the Inch to see what your prospects are.
http://www.ballisticsbytheinch.com/9luger.html

Jim Watson
03-13-2017, 09:32 AM
I haven't shot IDPA for a few years [I do miss it] so check this out for yourself. But I think you are allowed to use the longest barrel length allowed in your division to make power factor. So, if your 3" doesn't make it then you are allowed to test in the longer barrel. Almost every match I've been tested in they used a test pistol of the longest allowable length, not my pistol.

No longer the case.
Your ammo is chronographed in "the gun furnished by the shooter."
Now I have had one bedroll lawyer to say he could "furnish" a gun different/longer than what he is shooting in the match, but he would not get away with that on my range.

1986s4
03-13-2017, 09:45 AM
No longer the case.
Your ammo is chronographed in "the gun furnished by the shooter."
Now I have had one bedroll lawyer to say he could "furnish" a gun different/longer than what he is shooting in the match, but he would not get away with that on my range.

Thanks for the up date. That "lawyer" gives lawyers a bad name. Gamers, IMO, are folks who read the rules, know the rules and follow the rules but use imagination to find a better way, one not thought of by those who came up with the rules.

Pasco
03-13-2017, 02:52 PM
Thanks for the comments.

I have a chronograph, just haven't bought the gun! The data seems to show very marginal to make f125, that Ballistics By the Inch is interesting. I'm looking at the XD 9mm, it won't fit the BUG box. I'll just go out to the next local match and talk to some folks to ask around if this gun will do what I want. My son has the same gun in 40S&W and the 180, and 165gr bullets make about f136 if I recall, without even trying. Since I want to reload and shoot a lot, I want to use the 9mm since it's so common and a bit less costly to hand load.

Leroy
03-13-2017, 05:48 PM
If your shooting a local no one is going to chrono ammo. Just make a decent effort to make PF and roll with it. It won't help you win so don't worry about competitive advantage.

BN
03-13-2017, 06:50 PM
I found some old info on my handloads. A G-17 was 130.9 power factor, a different G-17 was 130.6 PF, a G-19 was 127.9 PF and a G-26 was 125.9 PF. A different load was 134 PF in a G-17 and 129 PF in a G-26. The only way to know for sure is chronograph. Most local matches don't chronograph, so I wouldn't worry too much about it. If you are shooting your sub compact in BUG, PF only needs to be 95.

Pasco
03-13-2017, 08:59 PM
Your comments got me to read the IDPA rules more closely. Running below power factor gets you a DQ but still allows you to shoot the match. There's my solution on the remote chance that anyone cares! I'm really just competing against myself anyway, just to get some stress shooting practice and fresh air. Maybe I'll post back once I get things in order.

Jim Watson
03-14-2017, 09:05 AM
As said, nobody is checking at Tier 1 club level monthlies. If your gun makes an appropriate bang and the poppers fall down, you are OK.
Not all Tier 2 small sanctioned matches will chronograph. Tier 3 will.

olstyn
03-14-2017, 06:00 PM
Are we talking about handloads or factory ammo here? As others have said, nobody's going to chrono your ammo at a local match anyway, so I'd say if you're buying factory ammo, go with 124 grain or heavier and just don't worry about it unless you have problems knocking down poppers. If you're going to hand load, you may have to do some tinkering with powders, bullets, and even cartridge OAL to get 125+ PF out of a 3 inch gun, but it should be doable; I got ~130 out of a 3.5 inch gun without having to work too hard at it. Half an inch may require an extra couple of tenths of powder to get there, that's all; just work up slowly with a chronograph and, as GuanoLoco said, watch for pressure signs.

All that said, you're also not going to be terribly competitive with a 3 inch gun; the simple reality is that smaller guns are harder to control in recoil, so you won't be able to shoot as quickly while maintaining accuracy as you would with a larger gun. If competition is one of your goals with gun ownership, you'll eventually want a larger gun. This is experience talking; I started out with a 3.5" compact myself, and it didn't take long for me to realize that it was a handicap in action pistol sports. I later bought the full size version of the same gun, and the first classifier I shot with it resulted in a better score than any I'd previously shot. YMMV, but it's something to think about.

Lomshek
03-14-2017, 10:48 PM
My Shield shoots a 147 grain polymer coated bullet 907 fps using 4.6 grains of HS-6 for a PF of 133. That same load in my M&P FS was 973 fps/143

Using 147 grain HST +p (it's all I could find at the time) I got 976 fps for a PPF of 143. In my M&P 9 FS it gave me a PF of 153 with 1045 fps.

I haven't crono'd it but would expect even WWB 115 to at least make 125 PF but it would be close. I don't have it recorded but seem to remember getting about 135 fps out of my Ruger 4.5" P94 with 115 gr WWB.

Pasco
03-15-2017, 02:45 PM
I'm getting into this to have fun. That sort of statement usually leads to serious obsession and an empty wallet.

It sure looks like not making power factor in a subcompact is the way it is, not that I live and die by power factor. With the comments above I am waffling on whether maybe a compact 4" barreled gun is 'better'. I really do need two....

Now the hand wringing starts on how to proceed. Off to the range to rent a gun or two I suppose. At this point I am willing to bet that a year from now I will have two new guns. I am a bit committed, I bought brass and 100 115 grn and 100 147grn bullets so I should have 200 rounds ready to go when this gun decision is done.

Jim Watson
03-15-2017, 02:57 PM
I might be out with the chronograph sometime this month.
I can compare a 3.5" SA UC to a 5" Loaded.

olstyn
03-15-2017, 05:25 PM
Now the hand wringing starts on how to proceed. Off to the range to rent a gun or two I suppose. At this point I am willing to bet that a year from now I will have two new guns. I am a bit committed, I bought brass and 100 115 grn and 100 147grn bullets so I should have 200 rounds ready to go when this gun decision is done.

Sounds like you'll probably end up somewhere similar to me - a compact and a full size of the same platform, the small one to carry and the large one to compete with. Glock G26/G19, G26/G17, G43/G19, G43/G17 are probably the "default" solutions for something like that, but there are plenty of other ways you can go and be happy with the results. HK has the P30SK/P30/P30L and the VP9SK/VP9/VP9L, Walther has the PPS/P99c/P99/PPQ/PPQ 5"/PPQ Q5, SIG has the 239/229/226, the SP2022, the P320, etc, and other reputable manufacturers have similar lineups as well. Hard to go too far wrong, to be honest, as long as you find something that works well for you. Also, 200 bullets is not going to last you very long, just saying. :)

Jim Watson
03-21-2017, 11:34 AM
OK, I ran some ammo over the chronograph.

9mm 115 gr Magnus JHP 1.095" 4.8 gr HP38
5" Colt 1225 fps f 140
3.8" P225 1154 fps f 132
3.5" SA 1123 fps f 129

9mm 147 gr Magnus FMJ 1.145" 3.6 gr HP38
5" Colt 942 fps f 138
3.5" SA 863 fps f 126

9mm 115 gr Federal American Eagle factory
5" Colt 1141 fps f 131
3.5" SA 1042 fps f 119

So you can make Minor power factor in short barrels within published load data, but econoball from cheapmart won't make the grade.

Pasco
03-21-2017, 10:27 PM
Good to see some data! Thanks for posting this. Not too worried about pf any more, close enough.

Tell me, do you find accuracy drops greatly going from the long to short barrels? I don't have any practical experience with this. Can training overcome the short sight radius deficit?

olstyn
03-22-2017, 05:38 AM
do you find accuracy drops greatly going from the long to short barrels? Can training overcome the short sight radius deficit?

I find that it's more about how much speed you have to lose in order to make good hits at distances > 10 yards. With a shorter sight radius, your sight picture is inherently less precise, so you'll have to slow down a bit more on longer shots. I'm not talking a lot, and how significant this effect is will vary with shooter skill level, but over the course of a stage or a match, it might be that little disadvantage that makes you get beaten by 0.5% vs beating that person by 0.5%.

Edit: so you know what level of shooter I am, I'm somewhere in the middle of USPSA C-class in Production, trying to gradually claw my way up to B. Last summer, I upgraded from using my 3.5" carry gun in USPSA to the 4" "full size" of the same gun (Walther P99c --> P99) and saw an immediate performance improvement as a result. It wasn't just about the sight radius (the full-size grip made a big difference, too), but the improved sight radius was definitely a factor. I shot the P99c in competition for several years, and while it definitely was a handicap, it didn't prevent me from having a lot of fun and learning a lot.

Pasco
05-27-2017, 06:55 AM
I know this a stale thread, but just a quick update and close. I picked up my new XD 4" 9mm a few days ago. Hope to go shoot this weekend. Thanks for letting me think out loud here and thanks for the comments. Now to select a holster, without buying five along the way... See you at the range.