[JAMESACERRA]

Hi Y'all
I've received a bag of 9mm Luger Winchester (new) brass 100ct and during inspection I put my caliper to them and found sizes from .749 (20) .750 (45) and .751 (35) of each.
Is this normal variations? Also would it be best to trim down the .751's to .750 for a larger store of .750's?
Also I'm going to be using HP-38 powder for my loads good/bad?
any assistance would be dandy.
This will be used in my Pre-88 FIE TZ-75 hope she likes the flavor lol.
Yours in service
James Acerra

Gun control is hitting your target

 

[zane grey]

New brass is like that. The different manuals list suggested trim lenghts from .751 "Lyman" to .744 "Speer". Trim them to .749 and have at it. The case mouths on those new cases are usualy out of square also, so a trim will put everything to rights. Checking some mixed 9mm cases I find OAL from .741 to .753. I also have an early TZ 75, more than 30,000 rounds through it and never any trouble. You gotta love those all steel guns. Good luck. Zane

 

[JAMESACERRA]

Great info Zane
Dandy deal, I'm new to the reloading gig. You would'nt happen to have the Owners Manual from your TZ would you?
I have the pre-88 with the slide saftey and dog-leg release

Gun Control is HITTING your TARGET.

 

[zane grey]

Hello---I still have the oiginal box with all the paperwork; but mine is a series 88. I shoot competition with mine and realy like being able to carry it cocked and locked. It also is factory ported. Good luck on your handloading. I am partial to the 147 gr. for knocking down steel targets.---Zane

 

[noylj]

Re: 9mm Luger Winchester (new) brass size variations .749 -

You have gotten near perfect brass.
Do NOT Trim them.
Separate them if you want and shot them. You may find the 0.750 or 0.751 brass to be just a shade more accurate than the other lengths. I have found that 0.750" is almost a "magic" length for accuracy/headspacing.
In my experience, the most accurate 9x19 loads require a 0.750" or longer case. If you trim them, you will have no chance of ever really seeing how accurate your gun can be.
The biggest problem with all pistol brass is that they are too short and end up headspacing either on the extractor or they end up seated too deep.
I save all my 0.750-0.752" brass for target loads at matches.
You trim rimmed revolver cases so the roll crimps are consistent. You do not trim rimless cases as they are supposed to headspace on the case mouth and it helps if they are actually long enough to do so. Taper crimp is not sensitive to case length like roll crimp.
You should be glad. New brass is generally even shorter than that. You have an excellent set of brass. The lengths are much more consistent than I have ever received with new brass and they are longer than I have ever received with new brass. They are all long enough that they will headspace very well. You should probably try to buy more from your source.
If I had some money, I would want to know where you bought them so I could buy 5k.