This may more properly go in the "ammo" category but, I'm posting it here because others of you are 625 afficianados. I had an extended range session today with my 625JM. I started off firing PRVI Partizan 230 gr. FMJ. The ammo and the gun worked superbly. I got some great groups at 10 yards and some really exceptional -- for me -- groups at 25.
Then, I switched over to Aguila 230 gr. FMJ. This is an ammunition that's made in Mexico. I understand that they have a great reputation for match grade .22 lrs. I'd picked up a couple of boxes of the stuff at a good price at a gun show last week. I've fired their .38 specials before (158 gr. SJHP) from my 686 with excellent results and I expected no less from the .45s.
As I fired the first group my immediate reaction was that the felt recoil from the rounds was much stronger than from the PRVI Partizan. It was almost as if I were firing +P ammunition. The group, at 25 yards, was terrible. Rounds were sprayed all over the target and I'm guessing that they added up to about a 10" group. When I attempted to extract the rounds (moonclipped, naturally) it was a no-go at first. I had to pound on the end of the extractor rod with a screwdriver handle in order to pop out the clip.
My thought was that, perhaps, the moonclip was deformed and that had caused the problem (I use RIMZ clips). So, I selected another clip, at random, loaded 'er up and fired another group. Exact same result. After extracting this clip, again with benefit of a screwdriver handle, I examined the spent cases from both groups. All were noticeably bulged.
I then switched over to another ammuntion (Atlanta Arms 230 gr. FMJ reloads) and the gun worked fine. Again, superb groups.
I'm guessing that the Aguila rounds were overloaded. I have no intention of using the remainder. Any of you have a similar experience?