hello;

just started loading for the 9mm. got some advice from someone that sells reloading supplies. he told me to load the cases as long as possible, as long as they feed through magazine. which i did.

in my p6 sig i had some failure to feed. hit the back (using the heel of my hand) of the slide and then the round would feed and fire. had an idea the recoil spring was weak.

just for the heck of it, removed the barrel and dropped a loaded case into the barrel and discovered some cases would not drop complete into the barrel. not all reloads had the same oal. also there were different styles of bullets.

think i got bad info. is the correct way to determine best oal for the 9mm is to keep seating the bullet deeper until the case drops complete into the barrel???? thanks for any input..

rp

Exactly what types of bullets and what OAL's are you using ?

Powder and charge used ?

The easy way: Load to the OAL listed in the manual. Max OAL should be 1.169 inches, but the companies producing load data pressure test the loads they recommend. I'm guessing the reloading guy you spoke to was trying to help you keep pressures down; using the OAL recommended in the data you're using should solve that problem and may give you better performance.

One problem I ran into when starting out with a wishbone press and Lee dies is that I was seating rounds to different depths depending on how I operated the press. This may not be the problem, but it may be worthwhile to measure your loads with calipers and see if this is happening.

having to seat remington 124gr. 9mm truncated bullets to a oal of 1.072". got this length by removing the barrel from pistol. started seating the bullet until the base of the case became flush with the rear of the barrel. is this a good way to determine oal.??

compaired something else. "eyeballing" the depth of two styles of bulles i'm using, the truncated bullet is not as deep into the case as the plated round nose bullet. different styles of bullets require different seatings to function in the p6. high pressure because of seating depth should be a none issue.

rp

Chances are the curved part of the bullet, the ogive, is contacting the rifling and that's why the gun didn't go completely into battery.

If it was rifle reloading with bottlenecked case the old trick was to soot the projectile part of a DUMMY! round with a wooden match or to color the whole projectile with a black sharpie markie.

Gingerly place the round into the chamber, close the bolt, pull the bolt back and again gingerly pull the round out of the breech area.

Then inspect the projectile to see if the soot or the ink was rubbed off by the start of the rifling. There could be 4 or more shiney coppery spots equally spaced around the bullet where the soot or ink was transferred to the rifling (the lands).

If that's the case, then the bullet is seated too long and should be seated deeper, say at least a 1/4 turn of the bullet seating stem at a time.

A trial and error process which is kinda a PITA.

And yes, you should have measured the dummy round before you chambered it and then measured it again afterwards.

If there are any differences in the two OAL's there is something wrong.

You either don't have enough neck tension or not enough crimp.

Having a bullet seated to deep or seat itself deeper under recoil into the case is bad ju ju.

As in KABOOM!

I tried to load in the 1.16 region... 1.158 to 1.162

There are always going to be some variance especially if using mixed head stamped brass.

1.16 and some change + is the max my magazines can take.

I always load up at least 5 dummy rounds, no primer, no powder.

Stuff them into a mag, and then insert the mag into the gun, with the slide locked back.

I then hit the slide release checking to see how well the slide goes into battery.

Then I cycle the rest of the rounds by hand through the gun. Again checking for jams and an out of battery condition.

Then I measure each of the rounds again.

You should consult a good reloading manual!

Another book worth mentioning is the ABC's of Reloading.

Having too short of an OAL will give you a KABOOM!



From a reliability standpoint, yes, seating the bullet out to the max allowed by your mag and/or your chamber, gives the round less room to deviate from its intended path from the top of the mag to the chamber.

Said another way a shorter round has more of a jump to make from mag to chamber and is theoretically more susceptible to getting hung up on the feed ramp.

Again, you should really consult a good reloading manual!

Before you take free internet advice as the gospel truth, 'kay?

I see what you're saying about truncated cone bullets. To echo the previous poster, though, I'd take a look at a manual (or a few - no such thing as too many) to see what kind of OALs are listed for truncated cone bullets of the same weight.

What lil bit I read is that 124 TC bullets do tend to run 1.07-1.10"

Be sure you start out with mild powder charges and work up.

One thing I do know is that a lot of P6's do not like hollow points and have to be modified to reliably feed them. The TC bullets are long the same profile.

You may want to find some regular RN bullets.

quote:

Originally posted by rp85:
having to seat remington 124gr. 9mm truncated bullets to a oal of 1.072". got this length by removing the barrel from pistol. started seating the bullet until the base of the case became flush with the rear of the barrel. is this a good way to determine oal.??

No, its not a good way to load. Please consult one or more loading manuals for correct load data.

I bought some Hornady jacketed hollow points for my HK USP. I could not get them to feed at all. I poured over all the reloading data I could find looking for minimum overall length. Finally found some data and loaded very close to the minimum length. I was using Unique so this wasn't as much a concern powder wise. They shot fine. The regular round nose FMJ's work fine loaded close to the OAL.