I was lazy and made a boo.
I had a very very accurate load in Lapua SRP that wasn't even showing pressure signs in 40C summer last year.
Had a few Sako LRP once fired brass so I thought meh, let's just load and shoot. (dumb dumb dumb)
It's mild but not really an obscene load, 40.0 gr varget and Scenar 123s seated 10 thou and it was a cold day (15C) QL gives me approx 57K PSI. first shot was absolutely fine, but a wee bit faster (3050 FPS) than last year (3000FPS). Didn't even felt like a still bolt lift but the ARC Nuke is so good at extraction that you can't really tell until its too late.
Second shot, blew a primer ... like really really bad .... Lucky the ARC action took it like it was nothing, was able to lightly tap the bolt handle and extract and eject but the case was in pretty bad shape. I've never seen anything like this so I immediately stopped and will pull all my remaining LRP loads.
I think it was a combo of laziness on these 3 factors
- The bullet was probably seated a little bit too deep creating extra pressure.
- The brass was obviously not as strong as lapua SRP - should have started 2gr lower
- The shoulder was bumped a little bit too much (4 thou) maybe ?
Also maybe an issue with powder contamination ? I'll definitely have to rework the load from scratch but luckily didn't seem to affect the action at all.
It look like a in-between from the center one and the one from the right ... that's like almost proof load territory and I have no idea how it could have been that hot. I use a ChargeMaster and double check with a GemPro so I'm pretty confident with my powder load.
Anyhow ... lesson learned. It's stupid, I don't even shoot past 1000 and I should have chase a lower node so it's not like I really need that extra 100fps.
I had a very very accurate load in Lapua SRP that wasn't even showing pressure signs in 40C summer last year.
Had a few Sako LRP once fired brass so I thought meh, let's just load and shoot. (dumb dumb dumb)
It's mild but not really an obscene load, 40.0 gr varget and Scenar 123s seated 10 thou and it was a cold day (15C) QL gives me approx 57K PSI. first shot was absolutely fine, but a wee bit faster (3050 FPS) than last year (3000FPS). Didn't even felt like a still bolt lift but the ARC Nuke is so good at extraction that you can't really tell until its too late.
Second shot, blew a primer ... like really really bad .... Lucky the ARC action took it like it was nothing, was able to lightly tap the bolt handle and extract and eject but the case was in pretty bad shape. I've never seen anything like this so I immediately stopped and will pull all my remaining LRP loads.
I think it was a combo of laziness on these 3 factors
- The bullet was probably seated a little bit too deep creating extra pressure.
- The brass was obviously not as strong as lapua SRP - should have started 2gr lower
- The shoulder was bumped a little bit too much (4 thou) maybe ?
Also maybe an issue with powder contamination ? I'll definitely have to rework the load from scratch but luckily didn't seem to affect the action at all.
It look like a in-between from the center one and the one from the right ... that's like almost proof load territory and I have no idea how it could have been that hot. I use a ChargeMaster and double check with a GemPro so I'm pretty confident with my powder load.
Anyhow ... lesson learned. It's stupid, I don't even shoot past 1000 and I should have chase a lower node so it's not like I really need that extra 100fps.
