Loading up some pretty short OAL pistol rounds ...

[Lead Waster]

Hi guys, I have a PPQ and some CZs and these things have a really short throat (I had considered buying a throat reamer to fix that, but ... nah)

I also bought some SNS Casting 124 gn rounds nose 9mm bullets...and these things are like a cylinder with a half dome on top. Like take an empty toilet paper roll and put a ping pong ball on the top. So it's my fault I didn't get a sampler pack before ordering ... a lot of them (to save on shipping).

The problem is that the ogive is really far out there, since it's like a cylinder, the profile means that not much of the tip goes into the barrel before the rifling hits the bullet. I've loaded long 147s (flat points, but a long taper before full bore diameter of the bullet), but they tumble so I thought I'd try something else.

Like a dummy, I just figured ... OK, I'll just load these up tot he same OAL as I did my precision delta fmj 124s. (1.140), and I loaded 100 of them. So at the range, I load up, rack the slide, pull the trigger .. nothing. Oh, oops, the slides not in battery and ... hmm, I can't rack it either. Afte a while I gave up and the "range guy" grabbed a squib rod and poked it out. Weird, so like a bigger dummy, I put that round aside and rack the second round ... same thing. Well they shot well out of other guns, but not the PPQ, and at home I plunked some rounds in and they hit the rifling real quick (the rounds fit in a Lyman 9mm case gauge though).

So ... the OAL that works with these bullets is 1.060 which is .. quite short. However, since they are quite cylindrical, the base of them actually sits less deep than the 147s sit (ie even more space under the bullet for powder), but of course 124s use more powder than 147s for a given "power factor". (assume I'm shooting USPSA, which I am).

Is a short oal like 1.060 something to worry about (aside from feeding issues) or is the only really important dimension the space under a seated bullet?

I read on the Hodgdon website that a lightly compressed smokeless powder charge is not a bad thing (unlike a blackpowder charge with a lot of air space). I don't know if this charge will be "compressed" or not.

I worry because reloading books only show such short oals on much lighter bullets (like 90 gn). But again the shape of the bullet is kind of fat.

Thoughts?

NOTE: I have been hunting for an unloaded 124 Precision Delta bullet so I could compare the length of the bullet and the 1.140 OAL I used for it, versus the length of my new bullet to see if the amount of bullet in the case is the same or not. I don't have any numbers here.

Thanks!

[followingc]

My PPQ also has a really short throat. Factory Speer GDHP rounds will not fit. I found this out much like you did, jamming a round in the barrel. After a round did not chamber, I retracted the bolt, ejected the case, and left the bullet jammed in the barrel.

I ended up with the following for MY 5" PPQ:

115g Hornady FMJ - 1.13"
115g Hornady HAP - 1.075"
125g Speer GDHP - 1.070"
124g Berry's TMJ - 1.064"

This leaves me at least 0.010 off the lands. I worked up all loads and didn't see any pressure issues and they all shoot the same out of my P226, which measures 0.075" longer than the PPQ.

I got into the habit of measuring every new bullet type I reload to be sure. As you probably know, measure from muzzle to face of bolt. Drop the pill into the barrel and measure from muzzle to bullet nose. Subtract those and that's your OAL jammed into the lands. I subtract a minimum of 0.010" from this, plunk-test to be sure, and I'm good to go.

[jdogg2000]

I have to load rounds for the PPQ shorter than the CZ as well. I tried the SNS and Blue Bullet 125 grain RNs and they both passed the plunk test at 1.09" for me in both barrels. Functioned fine and chrono'd fine as well. ACME has 124s with a different profile that I can load slightly longer at 1.10", maybe even longer. I have seen others load as short as 1.060" and they seem to be fine.

[rsrocket1]

What is the seat depth of your rounds (how deep is the base of the bullet going into the case)?
What powder and how much are you using?

My Lee 356-120-TC's have a COL of 1.05" - 1.07" based on the charge of Unique which gets about 5-8% compression. With that COL, the seat depth is 0.244" to 0.264". Great load, very consistent muzzle velocities and clean burning which is sort of an oxymoron for Unique.

You should always do a plunk test with the disassembled barrel of your gun when developing a new load. I plunk test every round I load since it only adds about a half to one second per round to perform the test. If/when the plunk fails, color the entire cartridge with a Sharpie marker (you probably only need to color the bullet itself) and press the cartridge back into the chamber. You'll see where the rub marks are or if it's the rifling that is causing the cartridge to fail the plunk test.

In my M&P's the culprit is a very tight throat and tight chamber, not the rifling. I have to size all my 40 and 9 bullets to 0.401" and 0.356" max if I want to have any of the driving band stick above the case rim.

[rmatt]

that is not a short load for a CZ. many people run an OAL of 1.010 in their CZ pistols. All depending on the specific bullet's ogive I run my xtreme, precision delta, montana gold and blue bullet all around that length.

147 gr bullets get 3.3 titegroup and 124gr bullets get 3.9 of same.

[Lead Waster]

I'm planning 4.3 gn of Win 231 to start, since that worked well for my 124 gn Berry bullets. Might as well start there.

What I did was seat a dummy bullet, plunk into (out of slide) barrel, then go shorter and shorter until the plunk test passed (When I was really close, I started crimping the dummy so it wasn't the rim hanging up).

I ended up with about 1.060 passing easily and 1.065 .... eh not so passing. So I decided to try 1.060.

I'll see what happens in the next week when I get a chance to try them at the range.

Thanks!

I always have trouble measuring from muzzle to breech and then muzzle to "pushed in by hand bullet seated on the lands".

I also tried to cut a case with a hacksaw and that was a laugh. Maybe I can dremel slits into a case.

So I went with trial and error ... seat, test, seat deeper, test, seat deeper, test.... etc.

[BEE]

I've loaded up a test batch of some Berry's 124gr Hollow Base Flat Points for my 75B SA at 1.040". I'm using HP-38 with a load range of {3.7gr, 3.8gr, 3.9gr, 4.0gr, 4.1gr}. I had no FTE's, FTF's, or any other issues. 4.0gr and 4.1gr gave me the best accuracy out of the bunch. I still need to test those loads again at a farther distance and with a rest and figure out which one I want to stick with. These flat points leaves nice clean holes on paper.

[Lead Waster]

OK, so I tested 4.2, 4.3 and 4.4 gns of Win 231 with OAL 1.060. Ran about 400 through the PPQ (and some through the CZ-75 SA). Fairly accurate at any of those loads (To be honest, at 7-10 yards I couldn't tell, I should try at greater range).

Unfortunatley I didn't mark my brass and just swept up a ton of other brass after the session. But no feeding issues. I need to mark and check the brass for pressure signs at the next outing, but seemed trouble free at 1.060. Looked weird in the magazine though.