5.7 x 28mm Frustration

[entropy]

I purchased a Ruger 57 about 14 months ago with the intention of reloading due to the price of the ammo. And being new to reloading didn't heed the advice this cartridge is a PITA to reload. But being this far in I don't want to give up. (Yes I'm living the fallacy of sunk costs.)

Using the Lyman 60th manual as a guide I started with 4.7 GNs of long shot pushing 40GR polymer tipped factory second bullets out of AE cases using CCI #400 primers. Then I started having feed issues. I figured it was a lack of powder so I went up to 4.8GNs of long shot, then 4.9. Problem persisted Today I tested 5.0 - 5.3 GNs at the range. The 5.0 and 5.1s functioned flawlessly. Then I tried the 5.2 and 5.3 GNs and the pistol wouldn't cycle correctly and pick up the next round. I had to push on the rear of the slide for the pistol to go into battery and pick-up the round. I would fire but it wouldn't eject the case so I had to cycle manually. This sometimes resulted in the next round in the magazine pushing up on the bottom of the round trying to enter the chamber resulting in a complete jam that required me to eject the magazine and clear the pistol completely. The only time the gun cycled normally was on the last round in the magazine.

So hoping the power of magical thinking could save the day I went back to some 5.0 and 5.1GN rounds I had in my range bag. Same result.

Just to make sure I sprang for a box of range priced FN factory ammo. I fired one round and it didn't cycle. I ejected the spent case and the pistol operated normally.

I've had these problems with cases I've just soaked and washed to preserve the coating and cases I've tumbled.

I use the lee resizing, seating, and crimp dies. I trim the cases to manual length each reload. I use the Sheridan slotted checker to confirm length, shoulder and diameter.

I'm looking for suggestions on what other variables I can try to eliminate or adjust.

My suggestion was going to be eliminate the caliber. I used to pickup the brass when I found it, and tumble it with the other range brass. Then I found out they are dry lubed, and tumbling ruined that. Now, I chuck them. (I do not have a 5.7)

Glad you got it figured out.

 

[Slamfire]

My suggestion was going to be eliminate the caliber. I used to pickup the brass when I found it, and tumble it with the other range brass. Then I found out they are dry lubed, and tumbling ruined that. Now, I chuck them. (I do not have a 5.7).

If you ever plan to have 5.7, it worth considering keeping those tumbled cases. And if you use them, leave the lube on the case after sizing.

This time of year, every weekend I can, I am shooting in matches. And in my smallbore prone and 2700 Bullseye I am shooting .22 Long Rifle. And those cases are completely covered in a waxy lubricant. The 22lr originated in 1887, well before the US Army demonization of lubricated cases. The US Army was lying about the defects of its low number M1903 receivers, which were blowing up, and yet was greasing 20mm cannon rounds during WW2. However, history aside, a good lubrication layer can be created by leaving case lube on the sized case. Or, as I did, apply Johnson Paste Wax to the finished round. I did this on my 30-06 and 308 match rounds fired in Garands and M1a's. Never had a case head separation. And another way I shoot lubricated cases is to put a drop of oil on the case shoulder. Regularly in 2700 Bullseye, I am adding drops of oil on the junction of bullet and case to my 45 ACP cases. This lubricates the mechanism, prevents jacket fouling, (and lead fouling) and actually improves function by dissolving crud in the chamber and breaks the friction between case and chamber. A clean and lubricated case will not stick to the chamber sidewalls, which increases thrust on the breech face. That is important when loads are just at the level necessary to cycle the pistol (and keep the bullet stable at 50 yards.) It is possible to download a bullet to the point it tumbles.