9mm OAL - Slide issues

[markm59]

Hello all,

I did a search this morning trying to find an answer but couldn't get right to the point. Here is the situation; I spent the last 2 weekends doing a major reloading evaluation on 2 new Springfield XDM 5.25's in 9mm. I have tons of data and found some great loads. It's the OAL that is bothering me.

When I load Montana Gold 124 JHP to an OAL of greater than 1.13" my wife has some issue with unloading with a round in the chamber. It feels like the bullet is in the rifling but I don't see any marks on the bullet. I thought maybe she wasn't gripping, depressing the beavertail correctly, but I'll have issues also. Now the rounds feed well, accurate as all heck, with no malfunctions out to a 1.15" OAL. My XDM does the same thing with a round in the chamber at longer OAL. I measured the case length of some of the brass and none are over the maximum length. And she needs to be able to "Unload and show clear", which she just can't do at the longer lengths.

I have a case gage, all rounds pass on that. I took the barrel out and dropped rounds in but I am not sure where the round should be positioned. Right now the case groove is centered perfectly where the extractor can grab it. I am use to 1911 barrels and have no idea how to judge the depth on the barrel test.

When I load at 1.115, no issues although accuracy is not as good.

I see all the posts and everyone seems to be loading out past 1.12" So I thought I would ask if anyone has some ideas on what's going on here.

What about cleaning, I have not cleaned the guns but they have only 500 rounds through each.

Thanks for the help.

[superdude]

does the round seem to get stuck, or feel even a little sticky, in the chamber? with the round fully inserted in the barrel, can you freely rotate it?

seeing rifling marks is not necessarily the ultimate criteria since the bullet might be slightly in contact with the riflings. the "rotate" test is probably the best. if the round freely rotates then the bullet is not contacting the rifling.

a good rule of thumb is to test at what overall length the round will finally not contact the riflings via the plunk and rotation test, then seat .010-.015 inches deeper. bullet nose shape is not always exactly the same and variations in it's shape can produce some rounds that won't pass the test. seating a bit deeper gives you a margin of error for nose shape and variation in OAL.

[reptoid]

What Superdude said!

With 124 gr JHP like MG, Hornady, or Zero I have to load at or shorter than 1.125" (actually 1.115" with the Hornady HAP) for my XD. With my Glock I can load out to .140"-.150"

[markm59]

Thanks guys. When I load longer than 1.12 the slide is difficult to pull back with a round in the chamber. Load out to 1.15 and my wife can't rack the slide at all and I have to work at it. Again this is a loaded round in the chamber.

It sounds like I just need to load at 1.115 as that worked without any issues. Both my Hornady and Lyman books quote 1.06 for this bullet weight/style.

Its too bad, accuracy is awesome at 1.15 and the gun functions fine but its the whole "unload and show clear" that my wife would not be able to complete in a match.

Appreciate the comments.

[Sarge]

also be aware that those rounds that got stuck may be shortened up due to jamming into the rifling. Measure them before shooting. Pressures can build immensely if you get bullet setback. Also know that you will reduce powder charges for shorter oals.

[superdude]

testing what will or won't pull free with the slide is not a good method. you need to take the barrel out and test your loaded rounds in it. they should fall in and fall out. do the rotation test. any guides for OAL are just guides. chamber dimensions vary and you have to test what your chamber will take. for additional info on OAL see:

http://38super.net/Pages/Overall%20Length.html

[markm59]

Thanks again guys. I'll take a look using the barrel drop test and see what it tells me. I take it the key is free rotation.

[superdude]

Thanks again guys. I'll take a look using the barrel drop test and see what it tells me. I take it the key is free rotation.

right. if the round sticks at all, even the slightest, you have a problem. it should be loose, even if you press the round in hard with your finger. you want to make sure that it doesn't contact the riflings at all.

loosey goosey, sticky icky. or something like that.

be sure to clean the chamber first.

[sroe3]

In my experience XD's have short chambers. I set OAL for the XD and it's good for all my other 9's.

[markm59]

Update - Problem resolved. Great advice guys, the key was rotating the round when doing the barrel drop test to check for contact. Never checked that before, in over 30 years reloading. Anyway my OAL needs to be 1.115 +- then everything works fine. This was the OAL I started my testing with so I have plenty of data at that length.

By the way, best powders in both XDMs were Unique, Titegroup and Autocomp, in that order. The Autocomp produced some superb accuracy in my wife's XDM, but didn't do as well in mine, which is why it was listed 3rd. Might be worth playing around with.

Thanks again to everyone...what a great forum.