The "stripes" on the fired cases are entirely cosmetic. They do not affect function in any way. I had an HK 91 back in the mid 80s, and still have some fluted brass in my plinking brass stash. Reloaded, it worked fine in the HK and in other rifles, both semi and bolt action.
I don't know if I would use it for match loads, but the flutes have no bearing on FUNCTION.
Dents, on the other hand, can be another matter. If your HK is only denting the shoulder, consider yourself lucky. Mine would whang the case body off the back edge of the ejection port, leaving not just a deep dent, but an actual sharp crease at the bottom of the dent.
I considered that much damage to render the case unusable. I got an "ejection port buffer", which was a hard rubber block, riveted to a spring steel clip that snapped over the action. You had to position it by eye so that the edge of the rubber block overlapped the rear edge of the ejection port.
This is no prevent dents, but it did make them shallower and without the sharp edged "slash" at the bottom of the dent. Those cases I did reload, without incident.
My rifle had a quirk I've never found on any other (although I haven't had other HKs to shoot, so I have no idea if some others will do it or not).
If you fired the gun as fast as you could, after about half a dozen rounds, it would rotate a fired case 180 and feed it into the chamber, base first. Instant jam.
If you fired the rifle at 2rnds per second, or slower, it NEVER did it. If you fired as fast as possible, it would do it nearly every time. Never saw any other kind of rifle do that...
I have been VERY impressed with the way this rifle stacks up against an M-1 or M-14.
I wasn't. While the M1A is not noted for being very reloader friendly, compared to the HK it a gift from above. I was looking for an M1A when I got my HK, and a couple years later, when I got my M1A, I got rid of the HK.
Specifically, my objections to the HK were, #1) the way it treated the brass
#2) Trigger pull of the M1A was better
#3) The HK safety could not be reached with the shooting hand, while maintaining a shooting grip. (this is a common "feature" of many European designed firearms. It did not appeal to me)
#4) while about 6" shorter, the HK weighed the same as my standard rack grade 22" M1A.
#5) the HK charging handle works in only one direction. The M1A op rod works both ways.
#6) the diopter sights on the HK were easy to use at 200 and beyond, I never could get quite the right sight picture with the 100 opening. M1A sights are more precise, and precisely adjustable by hand.
#7) the HK was a bit ammo sensitive. European ball worked fine, USGI did not. UNLESS oiled. Again, might have been my individual HK, I just don't know.
the ejection of the cases from NATO loads is, shall I say, Vigorous. The cases from my CETME (G3) go 30 plus Yards. The ammo for the original G3 was a very mild 7.62x51, not anywhere near the current military loads.
Vigorous is a good word. Cases come out HOT, dirty, and at warp speed. This is not a bad thing for the military. For the rest of us, it is less desirable.
A small point of order:
The original CETME was made in Spain. The G3 is German. They are essentially the same, but not identical. After WWII, during the years when German firms were not allowed to produce arms, a good portion of the HK design team went to Spain, and continued their work. They developed the CETME there, and it was made to run off the SPANISH 7.62x51, which is loaded lighter than the 7.62x51mm NATO.
When HK resumed German production, they made the G3 version of the CETME, having found that the hotter NATO ammo still functioned the gun acceptably. More ..vigorous than the Spanish ammo, but more than militarily acceptable.
I liked my HK, but I didn't love it. I love my M1A!
