And I thought CZ's had tight chambers...

[hAkron]

I picked up a Springfield Armory LW Compact Range Officer in 9mm (officer sized 1911 with some bells and whistles). I usually load a Montana Gold or a Berry's MFG 124gr RN bullet to about 1.135" OAL for my CZ's, which I shoot most often (and have, so far, had the tightest/shortest chambers in my collection). Today when testing out the new Springfield, I had a few rounds lodge in the action (gun wouldn't fully go into battery, and slide wouldn't move without wedging the edge on the shooting bench and smacking the frame with a non-marring hammer). I bought this gun used, and I'm waiting on SA to send me some kind of little clip that's required to get the guide rod out, so until then, plunk testing isn't going to be practical.

The problem rounds do fit into my Lyman 9mm case gauge without issue.

Anybody run into this issue with the SA LW Compact Range Officer? I'm sure it's got something to do with a match grade barrel and such, so I just need to figure out what will work in this gun and load special for it, but if anybody has already been down this road with this particular gun, I would be grateful for any insight.

 

[Tcruse]

Check the bullet seating depth, that is most likely your issue. I had to learn that lesson by first making the mistake of being too long with moving to FN shaped bullets.

 

[rcmodel]

I bought this gun used, and I'm waiting on SA to send me some kind of little clip that's required to get the guide rod out,

A paper clip or wire, or pin-punch will work as well as the 'special tool'.

What bullet are you using, exactly??

rc

 

[hAkron]

A paper clip or wire, or pin-punch will work as well as the 'special tool'.

What bullet are you using, exactly??

rc

The Springfield tool is a collar that captures part of the guide rod. Sadly there is no hole where you could stick a punch or a paper clip (or whatever) on Springfield's compact full length guide rod.

I had two different cartridges with me. Both types had issues. Berry's 124gr plated round nose and Montana Gold 124 FMJ Round nose. I've shot 4,000-5,000 of the Barry's in my other guns, and the Montana Gold were the last box from a case of those bullets (I think their case is ~3750 projectiles). Both loaded to the same OAL of 1.135"

Again, no easy access to the chamber until I can remove the guide rod, but I set my cartridges next to some factory Gold Dot defensive ammo, and my OAL was slightly shorter. From an eyeball measurement, my bullet didn't seem wider anywhere as compared to the factory ammo. I didn't shoot any of the factory ammo out of this gun (just compared it for reference after I got home from the range), but I was able to cycle it through the gun by hand.

I'm going to wait until the take down part arrives from SA and plunk test some of my rounds to see what my results might be. Could be an actual problem with the chamber, or it could just be ammo oversized for the gun.

I'm going to take some case rim measurement between my ammo and the factory stuff. I crimp lightly on the Barry's bullets to avoid damaging the plating. Maybe I need to go a little bit heavier.

 

[rcmodel]

Your 9mm ammo should be taper-crimped to .376" with .355" jacketed bullets.
.377" with .356" plated bullets.

Measured at the case mouth.

Then measure the bullet meplat just in front of the case for .355" / .356".
If you get that you probably need to seat deeper on the beginning of the meplat curve to get more full dis bullet inside the case to clear the rifling leade.

Rc

 

[hAkron]

Thanks for the info RC
.377 is what I'm getting on a few of my reloads that I've measured, including one of the ones that jammed the gun. I should know more when I can get the barrel out of the gun and visually inspect the whole chamber (rather then just peering in from the ejection port). If there is something wrong with the chamber dimensions, I have no doubt that a call to Springfield will get it taken care of.

 

[LiveLife]

Does a resized case fully chamber in the barrel?

 

[chris in va]

Having owned several CZ's the past few years I have learned to discard listed OAL and use the 'plunk test' on each individual gun. Once that OAL is determined I then adjust powder charge accordingly.

 

[Kp321]

I had to buy a Lee U die for my Springfield Range Officer. I had been using a Dillon sizing die which was not nearly tight enough for the RO chamber. No problems since using the Lee die.