Issues with 40s&w pc bullets

[Stevenvalleyky]

Ive loaded and run over 9,000 rounds of plated and over 1000 rounds of jacketed rounds thru my Springfield XD service but found some PC bullets locally cheaper than I can buy plated, so I decided to give them a try. But I'm running into an unexpected issue. I typically run AOL of 1.125-1.135. With these bullets, I cannot get them to plunk. I finally ran a couple short just to see and they will finally plunk once they are 1.112 or shorter. Also, I struggle to get them out of my barrel unless they are 1.112 or shorter. I realize this is below minimum AOL so I'm unsure how to proceed. These were made by Eggleston I believe and I've heard nothing but good things about them but I'm definitely having an issue. What is my remedy? Can I just reduce charges to compensate for the much shorter AOL? That seems like I'd be playing with fire. Maybe they are just not very compatible with this barrel. Im certain that the powder coat is hanging on the ring at the end of the chamber and that is also the reason that Im struggling to remove the longer rounds when I drop them in the barrel attempting to plunk them. The PC is soft enough to grip the ring pretty tight. This is the first issue like this that I've run across in several years of reloading. Any help is appreciated.

Last picture is to show 180 grain plated round fully plunked into the barrel.

 

[Walkalong]

There is no minimum OAL, only a max OAL. If they have to be that short to plunk, that, or shorter, is what you need to use.

When checking data you will have to take into account how much deeper they are in the case vs the same weight bullet in the data. Unfortunately there is no magic formula for figuring out how much that is.

 

[ATLDave]

I had the same issue when I switched from plated 220's in my 10mm to coated 220's. The coated bullets are simply thicker, so their shoulder/ogive interferes with the rifling at a shorter length than a similar-profile bullet that is plated. Walk', as usual, is right... if you want to use that bullet, you'll have to load shorter, drop down in powder, and work up again.

 

[Stevenvalleyky]

I don't have a lot of experience with using reduce charges in this situation. With an AOL of 1.125, starting load of Longshot is 6.3 grains with a Max load I'm 7.0 grains. If I have to run 1.112 for and AOL, how low should I start? I'm concerned of squibs and Kabooms and don't want to screw it up. I do appreciate the replies so far.

 

[ATLDave]

Are you chasing max safe velocity, or just something that will run the gun? The former requires at least a chronograph, and probably a call to Hodgdon.
The latter is probably easier... stuck bullets are only dangerous if you send a second round after them, so you can drop well down* and, as long as you are shooting in a place where you can see every bullet hole, you can test lower loads with a pretty decent level of safety. Also, the deeper seating will help build those early pressures to ensure good ignition, so chances of some kind of weird half-start are low, and you might even see better SD's.

You could work down with your OLD projectiles, figure out at what level you start having issues (far more likely to be failures to cycle than stuck bullets, but work carefully and CONFIRM A HOLE ON EVERY SHOT). Make that your start load for the shorter rounds, and work back up, again watching for stuck bullets.

Or you could just call Hodgdon. They might help you out!

* In straight-walled pistol cartridges. Dynamics may be more complicated in bottleneck rifle rounds.

 

[Wreck-n-Crew]

Its not unusual to have a bullet that hits the rifling causing you to shorten COAL. I have a 125gr Lee mold that ( after powder coat ) needed to be set to 1.075 to consistently pass a plunk test.
Needless to say it drove me crazy and though i have some limited OCD it was more about getting a more elongated profile because they feed better from my experience. At least when we are talking about a rn profile.

The Lee 125gr bullet has a more rounded profile. To be honest though it worked fine once i got the COAL set. I just did not like it.

It boils down to the ogive on a 9mm bullet ( as well as most others) that determine the min seating depth needed to pass a plunk test ( in other words max COAL).

Im just saying the same thing a different way than what the others have already said. I digress....

 

[Texas10mm]

1. Is the old and new bullet profile EXACTLY the same?
2. Powder or poly coat can add diameter
3. What are the bullets sized to?

 

[Stevenvalleyky]

ATLDave, just looking for it to cycle the gun, not concerned much with velocity.
Texas10mm, there is no old bullet profile, this is the first time Ive ever bought PC. All the others I shoot in 40s&w are different brands, weights, and bullet profiles. They measure .4015.
I appreciate all the advice guys. I think Im gonna set them deep enough to plunk then load a few 3/4 of a grain below the start charge and see how they do.

 

[Walkalong]

I typically run AOL of 1.125-1.135. With these bullets, I cannot get them to plunk. I finally ran a couple short just to see and they will finally plunk once they are 1.112 or shorter.

I don't think that small decrease in OAL would necessitate going under the starting load. I would be comfortable using the starting load.

 

[Stevenvalleyky]

Thank you Walkalong, that's the exactly the kind of information I was wanting to hear. I had no idea how much I should drop it and was thinking that may not be nearly enough or maybe way too much. Your reply helps ease my mind.