358Rooster
CGN Regular
- Location
- Central Saskatchewan
Hey guys, thanks for all the comments. I've just buzzed through all this and will try to respond to everything.
The barrel was not removed to cut & crown - the action was held securely in the spider at the back end of the spindle tube and the lathe is just short enough that 21-3/4" of barrel length ended up about .100" in front of the faces of the jaws. The barrel on this thing is heavy enough that you'd have to be an orangutan with a snipe to distort it in any way. I very much trust this guy - his work is as exemplary as his integrity.
There are no noticeable lumps or bumps or slack spots in the barrel as I run a brush or patch through it. Accuracy has been very good (at least as far as I'm able) since then with the Scenar and SMK load testing I've been doing.
To reiterate, same lots of all the same components as last fall. I even weighed several charges as I pulled them to see if there were any variations in that - there were none. Now, I need to clarify something here; looking at my notes again, my loads last fall were 45.8 gr. H4831SC and the little bit of testing that I had done showed decent accuracy between that and the next charge of 46.1 (I tested clear on up to 47.0 with only the highest charge showing pressure). So I decided to go with 46.0 thinking that I should be safe beyond a doubt. Maybe this 0.2 grains made the difference?
Another thing I failed to mention is that I hadn't cleaned the rifle since last fall and when I got it back, I just went and shot 25 rounds on April 2nd. Yes, things appeared hot but not overly concerning. None were shot over the chronograph (just needed to finally get some trigger time in). My notes say the temp that day was +14C. After that session, I cleaned the snot out of the barrel due to the smithy's notable expression of disgust with me (he's a devout BR nut). The chronograph was set up for the next session where I ran into issues. I realize that this scenario (dirty barrel = okay, clean barrel = pressure) contradicts conventional though but this is how things went down.
As for the questions about the chronograph, yes, there are always variables there. I can't honestly say if the same amount of sun was out the other day as there was last fall but given my experiences with this machine, every day is a bit different. I don't trust it to give me 100% reliable readings every time but the chronograph didn't cause the increase in pressure.
I'm dead certain that I must have missed something (other than the .2 gr. increase) and that this can otherwise be reasonably explained but I can't for the life of me identify that variable. Maybe I was on the ragged edge already but you'd think that it would have shown with subsequent increases last fall. I've since switched back to H4350, as I've finally obtained a bunch of it now and my mild surplus of H4831SC can go back to feeding the .284. I had pretty much resigned to (what I thought would be necessary) using a faster burning powder in the shorter barrel but since I had decent loads already, I'd just go and shoot after the long winter.
At any rate, it's really no big deal - I've noted all this and will not be returning to that load in the future. So long as this thing performs well with the new loads I'm actually taking time to develop now, I'm happy. I just thought some of you could provide some logical insight so as to ease my brain hurt.
Thanks guys!
Rooster
The barrel was not removed to cut & crown - the action was held securely in the spider at the back end of the spindle tube and the lathe is just short enough that 21-3/4" of barrel length ended up about .100" in front of the faces of the jaws. The barrel on this thing is heavy enough that you'd have to be an orangutan with a snipe to distort it in any way. I very much trust this guy - his work is as exemplary as his integrity.
There are no noticeable lumps or bumps or slack spots in the barrel as I run a brush or patch through it. Accuracy has been very good (at least as far as I'm able) since then with the Scenar and SMK load testing I've been doing.
To reiterate, same lots of all the same components as last fall. I even weighed several charges as I pulled them to see if there were any variations in that - there were none. Now, I need to clarify something here; looking at my notes again, my loads last fall were 45.8 gr. H4831SC and the little bit of testing that I had done showed decent accuracy between that and the next charge of 46.1 (I tested clear on up to 47.0 with only the highest charge showing pressure). So I decided to go with 46.0 thinking that I should be safe beyond a doubt. Maybe this 0.2 grains made the difference?
Another thing I failed to mention is that I hadn't cleaned the rifle since last fall and when I got it back, I just went and shot 25 rounds on April 2nd. Yes, things appeared hot but not overly concerning. None were shot over the chronograph (just needed to finally get some trigger time in). My notes say the temp that day was +14C. After that session, I cleaned the snot out of the barrel due to the smithy's notable expression of disgust with me (he's a devout BR nut). The chronograph was set up for the next session where I ran into issues. I realize that this scenario (dirty barrel = okay, clean barrel = pressure) contradicts conventional though but this is how things went down.
As for the questions about the chronograph, yes, there are always variables there. I can't honestly say if the same amount of sun was out the other day as there was last fall but given my experiences with this machine, every day is a bit different. I don't trust it to give me 100% reliable readings every time but the chronograph didn't cause the increase in pressure.
I'm dead certain that I must have missed something (other than the .2 gr. increase) and that this can otherwise be reasonably explained but I can't for the life of me identify that variable. Maybe I was on the ragged edge already but you'd think that it would have shown with subsequent increases last fall. I've since switched back to H4350, as I've finally obtained a bunch of it now and my mild surplus of H4831SC can go back to feeding the .284. I had pretty much resigned to (what I thought would be necessary) using a faster burning powder in the shorter barrel but since I had decent loads already, I'd just go and shoot after the long winter.
At any rate, it's really no big deal - I've noted all this and will not be returning to that load in the future. So long as this thing performs well with the new loads I'm actually taking time to develop now, I'm happy. I just thought some of you could provide some logical insight so as to ease my brain hurt.
Thanks guys!
Rooster
