COL on 9mm

Plink

Plink

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OK, trying my hand a 9mm for the first time. I've re-loaded for rifle, but this is the first time on a pistol round.
I measure one of my factory loaded 9mm's in 125gr at about 1.150, and I'm reloading 125gr FMJ as well. I see recipes that call for COL at 1.090, that seems AWFUL short to me.
I'm trying out HS6 at 6.5 gr (the bottle suggests 6.8 for a 124 gr) as a starting load.
All the reloaders nest recipes have COL at 1.090 as well. It seems REALLY short if you ask me.
Any suggestions on COL and a HS6 recipe for this round?

Also, when you crimp, should it be a really small crimp for 9mm, or, a deeper crimp.

Thanks folks.
 
As undertaker said, you must consider the OAL that will fit into your pistol. Take the barrel out and drop the bullet in to make sure it fits, regardless of OAL you choose. Also remember that OAL depends on the type of bullet. Flat and/or hollow points will usually be seated to a lower OAL in order to fit correctly. I often shoot 124gr FP, with the OAL at exactly 1.09. I have 124 gr round nose bullets that I seat to around 1.12 to 1.13, depending on the application. Regarding crimping, just make sure to remove the flare you created in the flare step. Measure it with your caliper. You don't want to deform the bullet at all. I don't mind mentioning it, but a mistake I made early on was to over-taper my 9mm. And absolutely make sure you do not 'crimp' it like you would to a 44mag bullet into a cannelure. Just a gentle snug of the taper back into spec.
 
OK, good info. I'll check that out today with the pistola barrel. I assume it should just "touch" the lands and grooves?

If there is to much crimp, what does it do?
 
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Plink,

The case OAL is, as stated by benchgrinder, determined by the configuration of the bullet. Some round nose jacketed (and lead) bullets have a shorter shoulder to tip measurement than others and are generally seated a little deeper.

Factory 147 grain American Eagle or similar jacketed flat tip (truncated cone) are great loads. You might want to avoid a 'hot' set up unless you're trying to meet an IPSC power factor. If you buy factory 125 grain jacketed ammo for a Chrono comparison to your hand loads, be aware that the fps of factory stuff could be all over the place. Go to the Hornady load information booklet - online - to get some excellent starting loads.

Crimp is important for consistency. In my sport, we shoot unmodified, out-of-the-box 9mm's (Duty Pistols) and super modified 9mm's (Distinguished Semi-Auto's) at distances up to 50 yards. The top shooters put rounds into the 10 and X ring on a B-17 target and home-grown loads are truly excellent performers. All these re-loads have a "factory taper crimp" to insure consistency.

By the way - one of the favored loads for 9mm is 3.4 grains of UNIVERSAL CLAY's with a 124 grain lead cast, round nose bullet. This smaller amount of fast powder burns up with no left over debris. Very consistent, very dependable. Very, very accurate.

The search for the perfect load continues... Good Luck.
 
Plink said:
I assume it should just "touch" the lands and grooves?
If there is to much crimp, what does it do?
Click to expand...

Setting the bullet to just 'touch' the rifling of your pistol barrel might in some circumstances end up being the wrong thing to do. I can't say from experience, but I have read that if it's seated too close, it may spike pressure and 'disassemble' your gun. It's not like a rifle reload where it is desirable to seat the bullet close to the lands and groves. I'm sure there other others on this forum who could give more information on this.

As for too much crimp, you might find the bullets 'tumbling', which is also called 'key holing'. There could be other issues as well.

As for using a factory die crimp (Lee and Redding make them, I use them from both companies), I highly recommend it. Taper crimping, or 'full crimping' for revolver loads really should be done in a step that is separate from seating the bullet.
 
OK, until I can test these at the range this weekend, I'm going to basically duplicate my pre-rolled rounds length. plus a "little" bit. Factory are 1.050, I'll go 1.060 for now, see how that works.
I'll muck about with exact length.
I have the Lee set of dies, and it has the adjustable crimp tool for the final stage. I must say it does a good job of making the round look just like a pre-rolled!

Thanks for the info gentleman.
 
Assuming that you are using a 124 FMJ RN(and not a hollow point or flat point,a good(what the manuals say)LOA is 1.130.

You have to be very careful loading loading 9mm P to a shorter LOA,as the case capacity is very limited and pressures go up very rapidly with deeper seating.

HS6 is a good powder for the 9mm,you could probably start at a lower load for your first reloads however.Tightgroup works very well in the 9 as well

A small amount of taper crimp (if you hold the loaded round flat against a ruler you should see a tiny bit at the case mouth)is also a good idea.Overcrimping can lead to loose bullets and bullet setback,something to avoid in the 9
 
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those specs you see in reloading manuals and websites are minimum OAL, you can load it more if you want just do go below the min. Just remember max OAL for 9mm is 1.169"....Some guns will not feed or chamber longer OAL bullets I had a gun that would not chamber a 138gr bullet when loaded to more than 1.100"...

as for crimp I like to see the bullet imprint on the brass (see where it ends)
 
Plink- I noticed in your first post you said the bottle of powder said "start" grains was 6.8 for 124 bullet.....that is MAX load data....reduce by 10% to start. I was shooting HS-6 at 6.4 with 124 Frontiers, worked well. COL was 1.130. Go to Hodgdons web site for some good data. They give COL of loads as well. Cheers
 
As to the crimp ONLY remove the belling you place upon it. If you start to roll crimp what is essentially a straight case (the 9MM is a tapered case) you will actually see a loser bullet/case fit. The brass tends to spring back while jacketed/lead bullets won't. The bullet in the 9MM like in the .45acp is retained by case tension not by the crimp.

Both Unique and Win 231 are also good powders to use in the 9MM. I prefer Win 231 only because it meters better in my Dillon powder die.

As to OAL I would back off the max OAL you have determined by inserting the cartridge into your barrel (Remove barrel from slide to do so) a few thousandths of an inch. You are using hobby equipment and it is not uncommon to have cartridges vary in length by a thousandth or two. The last thing you need is to have your cartridge length at max for your pistol and have a round a couple thousanths longer than max tie you up. Really ruins your day if it happens in a match.

Take Care

Bob
 
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