A shaky hand from the past [9mm reloads]

[Elric]

Came across some 9mm lead RN reloads, most likely from someone that shoots where you never run out of ammo and there's no brass calls...

Suprised me that the rounds would not chamber willingly in a Ruger P85. Whipping out my trusty Starrett 799, the mouth diameter is .380-.379, so if you really wanted to, it would chamber. Just not fully confidence inspiring. Uniform, but it coulda been a wee bit smaller, say .375 or so. The other thing is the case lenth of about .740, that is less than the .750 chamber. Though he might have shot these cases a lot.

 

[Brad]

Some guns have tight chambers. I know that the Taurus owned by my daughters BF won’t accept rounds that my CZ eats all day long.
Case length on 9 mm is all over the place. I don’t even measure them because it would just bug me. Ignorance is bliss.

 

[358156 hp]

9mm RN in particular are sensitive to the diameter of the bullet nose just ahead of the case. It could be that the bullet nose is getting hung up at the origin (throat) of the rifling. If you have a bullet profile that somewhat mimics 45 ACP ball profiles, this is likely your problem.

 

[fiver]

375 would be 10 thou brass and 355 bullets. it wouldn't even leave room for case expansion.

 

[Missionary]

Sort of reads like someone was using cast slugs for the 9 Makarov. Maybe was trying to re-load for his PA-63 and had a DUH afternoon

 

[JonB]

Vintage cast bullet ammo?
Maybe the bullet grew a wee bit as it aged?
I have a batch of 45acp LRN ammo that I loaded a long while back and now they won't reliably chamber in my Ruger. I've been shooting them in my 625 (without Moons), and I still find about one out of ten, are difficult to push into the cylinder. Dang, I still have at least 400 more to shoot before they are gone.

 

[Elric]

The bullet mikes .355 just outside of the case mouth, the case mouth is .379

.355 plus maybe .019 is .374, which should... wait. Case head is .384, let me check, maybe the head is swollen.... supposedly a head diameter of .391 is in-spec?

Looking at the bullet [beautifully cast], there is a straight section that extends about .10 PAST the case mouth before it starts the ogive up to the tip. Huh. All Win brass, I assume matching.

One end of the box, OAL is 1.009, case mouth .379, the end I was looking at the OAL is @ 1.128
Just picked one out of the center, .376 case mouth, 1.11 OAL, plunk! But the short one stayed high like the last one.

Taper. Though that first one seems a wee bit short.

Oh, little note in the box. 124gr RN Laser Cast, HS6, 6.5gr, CCI 500 11-15-99

 

[L Ross]

Got me curious as I just pulled the handle a bunch of times yesterday on the Dillon set up for 9 m/m. I used Magma 130 gr. RNFP sized to .357" and double checked for growth before starting. I test fired some in the HP before getting deeply committed and they went through just like used corn through a goose.

Took. a mic to them and as they are mixed head stamps with the smallest being .379" and the fattest .381". I do not trust 9m/m with small bullets, nope, not at all.

 

[Elric]

All men have a fear of getting deeply committed.

It would seem the P85MKII chamber expects strict discipline.

 

[CZ93X62]

RN ogive forms vary between makers on all autopistol bullets. Chamber throat and leade forms are usually short and abrupt, also. Those two factors don't always get along well. Generally, most autopistol ammo doesn't run well with significant front drive band or other full-caliber portions above the case mouth. Deeper seating may be the solution, but in the 9mm/40 S&W/10mm (and to a lesser extent in 45 ACP) deeper seating can prompt higher pressures with a given charge weight. I REALLY like having cartridge OAL specs in reloading data for these calibers, and I start low and work up with ANY new bullet. Lyman data for some of their cast bullets includes that info, and it is helpful in a number of ways on other bullet designs for a comparison of case volume taken up by the seated bullet, as follows--

(Bullet length + case length) - cartridge OAL = seated bullet length within case mouth.

 

[Elric]

I am looking for info on "Laser Cast" right now.

It does not seem to be the bullet's fault at all, the shortest cartridge will not chamber [1.006], but a round that is 1.116 DOES chamber. Taper at the case mouth sure looks to be the issue. It seems to be a very short taper as well, got to use care with the diagonal "jaws" of the caliper.

9mm 124g RN
https://oregontrailbullets.com/xcart/?target=product&product_id=85

Laser-Cast silver bearing alloy in a 9mm 124g RN .356 cast bullet.
Brinell Hardness: 15 This is the accual hardness tested with a LBT tester.

Oh, little note in the box. 124gr RN Laser Cast, HS6, 6.5gr, CCI 500 11-15-99

Looking at loads for HS-6 and lead, I think Uncle Dan was loading a bit on the hot side...

Hodgdon says
124 GR. BERB HBRN TP 6.0 to 6.6

124 grain lead in 9mm loads

www.rugerforum.net

 

[Elric]

Another box of reloads "50 Cartridges 9mm Ball M882", 124gr Laser cast, has mouths at a uniform .376, case length .745, head dia of .388, and they all plunk in the chamber. The taper on the first box looks like a roll crimp, where the case mouth "curls" inward. The crimp on this M822 is a smooth taper.

https://thearmsguide.com/wp-content/uploads/2014/07/Taper-Roll-Crimps-Figure.jpg