Bad reloads

[Blitzking]

Looks like I've made a major mistake, I recently loaded up some 75 grain bullets to test out in my 1 in 7 twist AR. Once I started firing I was getting 7 inch groups at 35 yards then my bolt would'nt go forward into battery.I found the problem was I was blowing primers and the primer cups had gotten up into the locking lug area.I tore this ammo down once I got home and discovered I was 3 grains over max.I checked my powder scale and it was way off. Im now wondering if I've damaged my upper? Bolt and locking lugs appear to be OK, I fired maybe 15 rounds before I discovered the problem.
I thought I was useing 748 powder I thought I had 24 grains turns out it was closer to 27 grains. I have since bought a digital scale!

[Damascus]

I doubt that you did any permanent damage. Have you closely inspected the chamber and throat area? Overpressure rounds can damage throats - but 3 grs. over shouldn't do any serious damage if you have a 5.56 NATO chamber (especially with a chrome lined bore), unless you fire a substantial amount of ammo. If you don't mind my asking, what scale were you using and what primers?
Are 7" groups @ 35 yds. common for your rifle?? :confused: What kind of rifle are you shooting?

[markm]

I doubt that you did any permanent damage.

permanent??

Is there such a thing as temporary damage? :p

[rockm4]

Looks like I've made a major mistake, I recently loaded up some 75 grain bullets to test out in my 1 in 7 twist AR. Once I started firing I was getting 7 inch groups at 35 yards then my bolt would'nt go forward into battery.I found the problem was I was blowing primers and the primer cups had gotten up into the locking lug area.I tore this ammo down once I got home and discovered I was 3 grains over max.I checked my powder scale and it was way off. Im now wondering if I've damaged my upper? Bolt and locking lugs appear to be OK, I fired maybe 15 rounds before I discovered the problem.
I thought I was useing 748 powder I thought I had 24 grains turns out it was closer to 27 grains. I have since bought a digital scale!

I've been reloading 98% of all that i shoot in my personal weapons for some38 years and have hot loaded a few rounds in different calibers. If the weapon is in good shape 3 grains over X 15 rds. shouldn't hurt anything.

[Blitzking]

I doubt that you did any permanent damage. Have you closely inspected the chamber and throat area? Overpressure rounds can damage throats - but 3 grs. over shouldn't do any serious damage if you have a 5.56 NATO chamber (especially with a chrome lined bore), unless you fire a substantial amount of ammo. If you don't mind my asking, what scale were you using and what primers?
Are 7" groups @ 35 yds. common for your rifle?? :confused: What kind of rifle are you shooting?

No 7 inch groups don't happen with my rifle, But 3 grains overcharge and primers blowing out I figure proably contributed to the crappy groups.
I do have a 5.56 nato crome lined barrel PK firearms Upper AR.
I pulled the bullets and reloaded to 24 grains, Groups tighted up nicely.

[jmart]

Just consider your bolt and barrel HPT tested.

What relaoding scale, how did it get so out of whack that you loaded three garins over? Something's not computing?

[Damascus]

permanent??

Is there such a thing as temporary damage? :p

My bad - poor choice of words. By "permanent" I meant "damage that's not fixable". ;)

@Blitzking - Good, I figured the 7" groups were caused by the overcharged ammo, just wanted to make sure. Also, what kind of primers are you using?? (A 3 grain overcharge shouldn't blow a good, tight magnum primer)... but anything's possible when reloading..

[jmart]

My bad - poor choice of words. By "permanent" I meant "damage that's not fixable". ;)

@Blitzking - Good, I figured the 7" groups were caused by the overcharged ammo, just wanted to make sure. Also, what kind of primers are you using?? (A 3 grain overcharge shouldn't blow a good, tight magnum primer)... but anything's possible when reloading..

That's about a 12-13% overcharge. Not good.

[Blitzking]

The powder scale is a RCBS it seems the slide bar deal wasen't locked on 20, it was cocked over to the 25 side. I didn't notice

[Blitzking]

My bad - poor choice of words. By "permanent" I meant "damage that's not fixable". ;)

@Blitzking - Good, I figured the 7" groups were caused by the overcharged ammo, just wanted to make sure. Also, what kind of primers are you using?? (A 3 grain overcharge shouldn't blow a good, tight magnum primer)... but anything's possible when reloading..

these were winchester primers and winchester case's. every thing looks fine