9mm JHP Sticking on Ramp

AzAfshin

I've been using a batch of JHP bullets for reloading and when I fire them about 1 out of 20 won't feed into the barrel. They just stick up at an angle in front of the feed ramp and the slide just puts a dent in the side of the shell due to the jam.

Could this be caused by the OAL being smaller than it should be? Before I spend a lot of time and effort on polishing the feed ramp I'd like to know if there are any obvious things I'm missing.

As added info, to determine the OAL, I do the barrel plink test (drop the loaded bullet in the barrel until it falls in freely and makes a plink noise, then go another .005 shorter).

62fuelie

The nose shape of the bullet can have a big effect on reliable feeding. If the majority of your loads (19 of 20) are feeding you might want to check the OAL of the rounds. 9mm brass is notorious for the variations in case wall thickness, especially at the mouth. I taper crimp all of mine by running them into a carbide sizing die until they are just snug. This will keep the bullets from moving during firing and feeding and hold the OAL. A little crocus cloth polishing on the feed ramp can help, too.

AzAfshin

Actually I do use a Lee factory crimp die to crimp the rounds. I just feel that if the OAL is too short then when the slide is pushing the round out of the mag and up the ramp the nose of the bullet would hit the barrel shroud a bit later than it should, hence the bullet stay pointing up rather than point into the barrel and get pushed into the barrel.

charliemeyer007

Could be a lot things causing the issue. Does it feed round nose ball good? Have you tried different magazines. Some people tune the magazine to load which is tuned to the bullet. Too short could cause the issue or not short enough. How large is the flat at the opening, maybe try some with a smaller HP.

Are the jams always at the start or the last one(s) out of the magazine or random.

Is it a new gun or well broken in but not well on the way to worn out.
How uniform is your brass? Same brand and lot, all shot about the same # of times or some of everything. Felt recoil seems consistent round to round, or noticeable variations BLAN BLAM BLAM Squib jam.

perry shooter

If your bullet is lighter than others that work or powder charge is on the mild side The recoil impulse might be too weak to fully cycle the slide . If this happens the slide hits the base of the cartridge before the cartridge has moved up as far as it should in the magazine
to give the cartridge a straight shot at the barrel chamber.

EDIT Another way you can check to see if you have a weak or marginal load is the fact that if your pistol normally locks the slide back after firing the last round in the magazine and now some times it does not lock back this is the secondary result of a weak load

AzAfshin

Thanks Charlie and Karl. I knew there wouldn't be a simple answer, but now I have a laundry list of things to check.

Mobuck

"If your bullet is lighter than others that work or powder charge is on the mild side The recoil impulse might be too weak to fully cycle the slide . If this happens the slide hits the base of the cartridge before the cartridge has moved up as far as it should in the magazine
to give the cartridge a straight shot at the barrel chamber."

^^^^^^THIS^^^^^^^
That "1 out of 20" is a wee bit lighter charge or whatever causing the slide to catch the case in front of the base driving the case sidewise into the feed ramp.

NeoBlackdog

If the problem is as Perry and Mobuck have described then stiffer magazine springs should cure it. My wife had this issue in one of her pistols and this was the fix.

casper1947

As stated there are a lot of possible reasons. I would suspect the round just prior to the miss feed. But what is the COL of the problem round and how does it compare to the others? What is the mfg. of the JHP bullet? How is the powder measured? Are 9s the only pistol you load? etc about the actual load procedure? Just a few thoughts.

AzAfshin

The 9's are the JHP (115 Gr) from Montana Gold. I also reload their 45, but FMJ and have had no issues. These are the only pistol rounds I have reloaded so far (a total of about 4000 rounds). Rifle rounds I have reloaded are 300 Win Mag and 223 Rem (308 is next).

The 9's are my first reloads, so they are on the lower end of the amount of powder recommended, so it is entirely possible that there isn't enough powder to push the slide all the way back. I use my Dillon powder dispenser and can totally see it dispensing too little powder in 1 out of 20 rounds leading to this problem. I chornoed my rounds at a bit less than 1100 fps, so I have a bit of room to go higher in powder and see if this resolves the issue. As an aside, factory FMJ rounds have no problem in this pistol (CZ SP-01) and those chrono at almost 1200 fps.

iceracerx

Your 'plink' test has no bearing on OAL. A 9mm case seats on the case mouth in the chamber, just like the 45 ACP and other 'auto' cartridges.

AzAfshin

quote:Originally posted by iceracerx
Your 'plink' test has no bearing on OAL. A 9mm case seats on the case mouth in the chamber, just like the 45 ACP and other 'auto' cartridges.



I beg to differ. If the OAL (overall length) is too long the bullet engages the rifling before the case mouth gets seated so you won't hear a plink and the bullet sticks in the barrel. But if the OAL is just right (or shorter than necessary) then the bullet will not stop the case mouth from seating and making a plinking sound without any sticking.

iceracerx

Does your 'test' produce different results with 'truncated cone', 'semi-wadcutter', FMJ, Jacketed HPs, Lead HPs, etc? I'm willing to bet it would result in a different OAL for each different type.

It seems you need a reloading manual. Reloading is a science and doesn't favor guess work.

Of course, you are free to do as you please.

quote:Originally posted by AzAfshin
quote:Originally posted by iceracerx
Your 'plink' test has no bearing on OAL. A 9mm case seats on the case mouth in the chamber, just like the 45 ACP and other 'auto' cartridges.



I beg to differ. If the OAL (overall length) is too long the bullet engages the rifling before the case mouth gets seated so you won't hear a plink and the bullet sticks in the barrel. But if the OAL is just right (or shorter than necessary) then the bullet will not stop the case mouth from seating and making a plinking sound without any sticking.

AzAfshin

Yes, my test would result in different OAL's for different types of bullets. That's why manuals give different OAL's for different types of bullets also. That's also why I'm asking my question here to see if this test is reliable or not. Manuals don't specifically state what the OAL should be for the Montana Gold JHP which may have a different profile than a Hornady JHP. Based on prior feedback from other members here, and some verifications online, seems that the plink test is quite an accepted method for 9mm. But I wanted to make sure.

If the plink test is not acceptable, then what method is? Bear in mind that you can't have an OAL that puts the bullet on the lands and grooves as that would create a stickiness with the bullet that could result in high pressures when fired. Of course, you can't have a small OAL since that would create high pressures also. So I do understand there is science in here (that's a big part of why I enjoy reloading). The question comes down to, how to set AND measure OAL on a 9mm if the plink test is not acceptable for 9mm rounds given different bullet profiles?

243winxb

This is my guess quote: Have you tried different magazines. The round is coming out of the magazine to soon. i bend the lips in some.

noylj

In almost all cases, if the round jams the bullet at the top of the barrel, the COL is too short.
Your title said "sticking on ramp." In this case, a COL that is too long is almost always the case.
Do you start with a COL so long that it can't chamber and then reduce and, using the plunk test in conjunction with painting the bullet and case black, determine the longest working COL that fits the magazine and feeds and chambers using inert dummy round, thus verifying that any interference is due to the COL and not a case issue?
Just want to be sure.
IF you do this, and the COL is not working, you can always try a little shorter COL (though that will generally make the issue worse in my experience). Just watch for pressure or reduce the start load by 2%.
Depending on the bullet and barrel, I have a COL variance for 124gn JHPs from 1.025" to 1.125". Conicals tend to be able to be loaded longer than RN-JHPs.

Re: COL
Per Ramshot:
"SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH "COL"
It is important to note that the SAAMI "COL" values are for the firearms and ammunition manufacturers industry and must be seen as a guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as
1) magazine length (space),
2) freebore-lead dimensions of the barrel,
3) ogive or profile of the projectile and
4) position of cannelure or crimp groove.

Along with this, I include feed ramp angle

AzAfshin

Noylj, I said the bullet "sticks up in front of the ramp" not on the ramp. But based on what you're saying, sounds like the length may be too short.

You are right about how I do the plink test. Start with a long bullet which doesn't plink when dropped in (in fact, it sticks a bit in the barrel). Then keep shortening (half turns on the fine seating adjustment screw) until the round falls in the barrel with a plink and turning the barrel upside down allows the round to fall out easily without any sticking. Then I go another .005 shorter. I'm thinking that the .005 may be unnecessary and my half turns may have over compensated already.

Also, there are a lot of other good suggestions by other posters. I think the slide not being pushed back far enough may be a strong possibility. So I'm going to play with these two parameters in my next round of reloads and see what happens.