308 overpressure

[Tim-o-thy]

I’m not sure if should move this to the reloading forum. Little back story I had a trued remmy 700 action laying around and got a sweet barter deal on a 18” bart sendero type contour. I figured why the hell not. So I had around 1000 178 eld’s that my gas gun eats up! So I worked up a load (my gas gun likes 43.5 of varget in bulk Lc brass. But for bolt rifles I use lapua exclusively so I bought 300 cases and when to work I went up to 45gr per hodgdons website and got the lowest sd’s I’ve ever got in my life Sd:1 avg fps 2597. At 45g I was astonished. So I went home and loaded 60 more. And boom first few shots where fine then came extractor marks on the cases so I started over and can’t get any reasonable accuracy out of this gun at any lower charge weight. You guys have any ideas. Do I need to switch components? Also sorry for being so long winded-tim

 

[Tim-o-thy]

The crono

 

[XTR]

Is it grouping poorly or are you just not getting the ES/SD you are looking for.

If it's es/sd with an 18 inch barrel you arent going to be able to shoot far enough for ES/SD to make a whole lot of difference. They really don't matter much inside of 600 yards. If you want to talk about shooting an 18 to 1000 yards well... have fun.

Lose the chrono, do an OCW test from 42.9 to 44.1 in .3 increments. You should be able to get them into something like a node in the range of 43 to 44gr if you do a 300 yard OCW test. Load in the middle of the node and tune seating depth. What ever the velocity is, it is. Chrono it after you find the load.

 

[Rsadams]

Try cleaning the barrel really good and give it one more try IF the load is safe.... If not I would try some 168 or 175 Sierra matchkings or tipped matchkings before giving up or getting to frustrated.... There's not a lot of .308s that don't like the 168gr matchkings with a jump... You know how it is , a load that shoots good in one rifle doesn't meen it shoots good in them all... It's best to work up a different load for each rifle in my opinion , plus you get to go shoot.... Let the target tell you what shoots best , the crono is a great tool , but it's not everything....

If you're asking about the load being too hot , some pictures of the brass would be helpful..

 

[Tim-o-thy]

I’ve already processed and mixed the brass in but it had a perfect little circle extractor mark on it. I did a load work up for this rifle. I mentioned the other rifle more as a reason as why I had so many eld’s. And it’s nice when two rifles shoot the same projectile I do have a box of smk 168’s I’ll run a new work up of those. Have you tried 178eld’s before with any luck.

 

[Tim-o-thy]

Is it grouping poorly or are you just not getting the ES/SD you are looking for.

If it's es/sd with an 18 inch barrel you arent going to be able to shoot far enough for ES/SD to make a whole lot of difference. They really don't matter much inside of 600 yards. If you want to talk about shooting an 18 to 1000 yards well... have fun.

Lose the chrono, do an OCW test from 42.9 to 44.1 in .3 increments. You should be able to get them into something like a node in the range of 43 to 44gr if you do a 300 yard OCW test. Load in the middle of the node and tune seating depth. What ever the velocity is, it is. Chrono it after you find the load.

Thank you I’ll will give that try next week. What seating depth do you start your ocw tests with?

 

[DirtySteve]

What is your COL???? Also I have not come across a rifle that did not shoot 44.5 grs and a 175 SMK well....

 

[Tim-o-thy]

Is it grouping poorly or are you just not getting the ES/SD you are looking for.

If it's es/sd with an 18 inch barrel you arent going to be able to shoot far enough for ES/SD to make a whole lot of difference. They really don't matter much inside of 600 yards. If you want to talk about shooting an 18 to 1000 yards well... have fun.

Lose the chrono, do an OCW test from 42.9 to 44.1 in .3 increments. You should be able to get them into something like a node in the range of 43 to 44gr if you do a 300 yard OCW test. Load in the middle of the node and tune seating depth. What ever the velocity is, it is. Chrono it after you find the load.

What is your COL???? Also I have not come across a rifle that did not shoot 44.5 grs and a 175 SMK well....

I know they are 20 off the lands and under 2.845 because they feed reliably in magpul mags. But I didn’t write down oal for some reason.

 

[Rsadams]

I’ve already processed and mixed the brass in but it had a perfect little circle extractor mark on it. I did a load work up for this rifle. I mentioned the other rifle more as a reason as why I had so many eld’s. And it’s nice when two rifles shoot the same projectile I do have a box of smk 168’s I’ll run a new work up of those. Have you tried 178eld’s before with any luck.

No I haven't tried them I have had such good luck with the matchkings I haven't really tryed a bunch of different bullets in .308 even though it's one of my favorite cartridges to have fun with....

 

[Tim-o-thy]

No I haven't tried them I have had such good luck with the matchkings I haven't really tryed a bunch of different bullets in .308 even though it's one of my favorite cartridges to have fun with....

This is my third 308 to load for and the first time haven’t found a load in 100rounds I feel like I’m loosing my touch, or maybe 6-6.5 cartridges have made me lazy.

 

[Liven The Dream]

This is my third 308 to load for and the first time haven’t found a load in 100rounds I feel like I’m loosing my touch, or maybe 6-6.5 cartridges have made me lazy.

Possible ? 1-800- New-Barrel

 

[Ggmac]

Try different bullets and a little closer to the lands . Lower and start up .

 

[wkdickinson]

I’m not sure if should move this to the reloading forum. Little back story I had a trued remmy 700 action laying around and got a sweet barter deal on a 18” bart sendero type contour. I figured why the hell not. So I had around 1000 178 eld’s that my gas gun eats up! So I worked up a load (my gas gun likes 43.5 of varget in bulk Lc brass. But for bolt rifles I use lapua exclusively so I bought 300 cases and when to work I went up to 45gr per hodgdons website and got the lowest sd’s I’ve ever got in my life Sd:1 avg fps 2597. At 45g I was astonished. So I went home and loaded 60 more. And boom first few shots where fine then came extractor marks on the cases so I started over and can’t get any reasonable accuracy out of this gun at any lower charge weight. You guys have any ideas. Do I need to switch components? Also sorry for being so long winded-tim

I shot 1,000's of Berger 185 VLD in my 308 Win M70 Match Rifle with 46.0gr of Varget (Win brass, 210M primers), with no issues. I know that is way over what the Berger manual says, but so what, it worked fine for me.

 

[XTR]

I shot 1,000's of Berger 185 VLD in my 308 Win M70 Match Rifle with 46.0gr of Varget (Win brass, 210M primers), with no issues. I know that is way over what the Berger manual says, but so what, it worked fine for me.

That is a very hot load, as far as I recall it's well beyond what most F-TR guys shoot. I know WW has a bit more capacity (I wore out a few thousand of them a few yrs back) but thats pretty much the load recipe for the 155s with Varget in Lapua Brass that Palma shooters use.

 

[Liven The Dream]

That is a very hot load, as far as I recall it's well beyond what most F-TR guys shoot. I know WW has a bit more capacity (I wore out a few thousand of them a few yrs back) but thats pretty much the load recipe for the 155s with Varget in Lapua Brass that Palma shooters use.

Yes indeed 46 hrs. Of Varget on a 185 Berger .
Bolt Handle Bender .

I shot 44 grs. Of Varget behind a 185 Berger in SP .308 Brass 30” Barrel F/TR Rifle .

My Palma Rifles 32” Barrels Berger 155 HB 46 grs. Varget .

 

[rammac]

I shot 1,000's of Berger 185 VLD in my 308 Win M70 Match Rifle with 46.0gr of Varget (Win brass, 210M primers), with no issues. I know that is way over what the Berger manual says, but so what, it worked fine for me.

I recommend that absolutely nobody even tries this load. It's less than proof load pressures but it's still well over the SAAMI max avg. While a load like this will allow a very strong action to function it will also create stresses that will eventually make the receiver fail, it's not a question of will it create stress fractures, it's a question of when will those stress fractures make the metal fail.

 

[theallcineyes]

I had a very similar problem.

I tried 38 through 42.5gr IMR 4064, 165gr SST, LC brass, Win LR primers. 2.805 COAL. At 41.5gr, primers were flat as shit and extractor was ripping through rims. I had to reduce my powder charge to 39.5 to get this load to function in my rifle and those are only going 2225-2240 FPS.

Last weekend I pulled down the last few I had loaded up with IMR and tried Varget. Same brass, same primer, same bullet (for the work up)--I went from 41gr-45gr with no signs of over-pressure. The 43.9gr with 168 HPBTM load that shoots the best for me is flying at 2550.


I think we got a bad batch of 4064. (I bought mine in Dec '15) I'm just glad I only bought 1 lb because I'm not using it again.

 

[wkdickinson]

I recommend that absolutely nobody even tries this load. It's less than proof load pressures but it's still well over the SAAMI max avg. While a load like this will allow a very strong action to function it will also create stresses that will eventually make the receiver fail, it's not a question of will it create stress fractures, it's a question of when will those stress fractures make the metal fail.

I've read everyone's critique of this load with great interest, given that I never had any pressure signs - no bolt lift issues, ejector marks or primer indicators. I started using the load in the mid-90's and I'm sure it was a published load from a reputable source at the time. Exceeding the maximum recommended charge has never been a practice of mine.

Currently, on their website Hogdon shows the maximum Varget charge weight for 180gr bullets as 45.0gr., which 2.2% less than 46.0gr. I think we will all agree that bullet and powder manufacturers have gotten significantly more conservative in the last 25 years. So I don't think it's unrealistic to believe that 46.0gr may have previously been the maximum.

However, I was not and am not advocating anyone use the load! Rammac is probably right, it is likely too hot. Just sighting my experience.

 

[DennisH]

Every barrel is different and has it's favorite load. Same with COAL.

My 10 twist 308 loves the 43.5 to 43.9 (30" Bull Barrel) pushing the 185 Berger Hybrids. (Jag's). It's right at the "Edge", anymore powder, all the over pressure signs start showing up.

 

[hunter67]

Have you tried different brass. Sometimes LC and Federal brass can show pressure early. IMHO