338 Edge – Need Help with Early Pressure Signs

[nchunter182]

[FONT=&quot]I have just started working up a load for my Edge and am running into pressure signs I need help with. [/FONT]
[FONT=&quot]Some statistics on rifle and loads:[/FONT]

[FONT=&quot]30" Obermeyer 5R barrel 9.5" twist [/FONT]
[FONT=&quot]Chambered with long throat PTG reamer – .217" freebore and case length 2.855" [/FONT]
[FONT=&quot]Chamber neck diameter .3714"[/FONT]
[FONT=&quot]Stiller Predator action[/FONT]

[FONT=&quot]New Nosler brass – 2.465" headspace measured with Hornady .420" gauge[/FONT]
[FONT=&quot]Once fired brass is 2.467" headspace measured with same gauge[/FONT]
[FONT=&quot]Trimmed to 2.820 case length[/FONT]
[FONT=&quot]Neck diameter with seated bullet .3675"[/FONT]
[FONT=&quot]Fed 215M primer[/FONT]
[FONT=&quot]H1000 powder – recent lot# 1050713[/FONT]
[FONT=&quot]300 SMK seated .010" from lands gives COAL of 3.925"[/FONT]

[FONT=&quot]Loading one round at each to find max:[/FONT]
[FONT=&quot]Started out trying 300 NAB with H1000 88.5-93grs in ½ grain increments loaded -.005" from the lands. 88.5gr gave heavy ejector mark and moderate primer crater. Stopped shooting at 89grs due to heavy ejector marks. This load gave 2749fps. [/FONT]
[FONT=&quot]Tried 300 NAB -.010" from lands with H1000 83.5-85gr in 1/2 increments. Even 83.5gr showed slight ejector mark @ 2578fps. Shot to 85.0gr and stopped because of heavy ejector marks @ 2614fps. [/FONT]
[FONT=&quot]Tried 300 NAB -.020 from lands H1000 83.5-85gr in 1/2 increments. Again stopped shooting at 84.5gr @ 2599fps because of ejector marks. [/FONT]

[FONT=&quot]The high pressure signs I saw prompted me to switch to the 300 SMK. I thought the longer bearing surface of the NAB was contributing to the pressure signs.[/FONT]

[FONT=&quot]Loading one round at each to find max:[/FONT]
[FONT=&quot]Loaded 300 SMK -.010" from lands with H1000 87 to 92gr in ½ grain increments past 90grs. 87gs gave 2640fps and again ejector marks with moderate primer cratering. Decided – what the hell – kept going and checked case condition carefully after each shot to see if the condition worsened. It got worse with heavy ejector mark and some wiping of brass from the raised mark but I shot up to 92gs @ 2818fps. That's more like it but brass is taking a beating.[/FONT]

[FONT=&quot]Things I tried:[/FONT]
[FONT=&quot]Bought GO gauge to verify headspace. Bolt will close but very snug with one layer of Scotch tape on bolt face of gauge.[/FONT]
[FONT=&quot]Punched out spent primer and installed new on 92gr load case. Still holds primer but noticeably looser. At that rate I'll only get two loadings out of the brass.[/FONT]

[FONT=&quot]Can try:[/FONT]
[FONT=&quot]I have Retumbo – give it a go.[/FONT]
[FONT=&quot]Dump the Nosler brass and get Bertram. Probably well worth it in the long run but am I just masking a pressure problem? [/FONT]
[FONT=&quot]Get lucky and find some VV N570 and give it a try. [/FONT]
[FONT=&quot]Seat bullets further from lands.[/FONT]
[FONT=&quot]I have a box of Berger 300 Elite Hunter to try.[/FONT]
[FONT=&quot]Have yet to try a once fired case as I have 80 more unfired. Probably will not hold a primer after that.[/FONT]
[FONT=&quot]Reduce powder charge and live with it.[/FONT]
[FONT=&quot]Don't know anyone with a chrono to borrow…[/FONT]
[FONT=&quot]Stop over analyzing and keep shooting?? [/FONT]

[FONT=&quot]Hunting season is coming up and need to get something figured out soon. Long post but better to have info to go on. Below is picture of brass from 92gr load.[/FONT]

[FONT=&quot]Jay[/FONT]

 

[Broz]

Seat the SMK at -.060" and back off to 90 gr of H-1000 and work up. Or work back toward the lands and see if velocity comes up staying at 90 gr. Also watch what accuracy does at 200 yards. 92 gr with a 300 gr bullet is a stout load in summer temps and the 2800 fps is right on par. Usually with RP brass and a 300 gr loaded with 92 to 92.5 gr of H-1000 the brass lasted me 3 firings and showed slight ejector pin marks, a slight bolt lift but not much smear of brass.

Even with Bertram brass and 92.5 gr with a 300 Berger I get a shadow of an ejector pin and 2835 fps.

You will probably be able to run the Bergers with a little more charge and get a little more speed due to the shorter Bearing surface.

Jeff

 

[Broz]

One more thing. I have never used Nossler brass so I am shooting from the hip. Also it is hard to tell in a pic, but that 92 gr brass looks about right for the MAX load. But you will be running it right on the rev chip in summer temps and brass life will be short.

Jeff

 

[nchunter182]

Thanks for the quick response Jeff. I will be loading some rounds this afternoon and try them tomorrow morning. I still have just been shooting single loads at any given powder weight so have not yet seen how they will group. Once I find a charge I think I (and my brass) can live with I'll go to loading and shooting groups.

Jay

 

[highridge1]

I had all kinds of trouble with H1000 went back to my old reliable RL25 and problem solved. Lot to lot inconsistent and eratic velocity other guys have great luck with H1000 I am not one of them I would rather dump it on the lawn....

RL 25 I had better velocity, accuracy, and ES was way better only 6 fps on last Edge.I could comfortably run 2860 with no pressure issues in a 28 inch barrel.

Guys will debate this until they are turning blue but that is my real world results try H1000 and RL25 in 338 Edges, 338 RUM, 300 ultra. 338-378

As far as temp sensitivity I have not had any troubles with RL25. I know I few guys that run long range 338's and they are getting excellent results with RL25 shooting way past 1000 yards in Montana weather.

 

[Broz]

Don't dump the H-1000 I will gladly trade you RL 25 for it, and some 22, 19 and what ever else I have with RL on it. I am one of those guys that could not deal with the RL velocity / temp change for long range.

Jeff

 

[nchunter182]

Highridge1 - I do have just under 1 lb of RL25 to try if all else fails. But I also have 16lbs of H1000 so I need to make it work!

Jeff - Went out and shot today. Loaded one round each of H1000 90-92grs in 1/2gr increments. Seated the 300SMK .060" of the lands for a COAL of 3.865". Unfortunately today I guess my chrono decided to be finicky about the muzzle blast. Even though it was set up 20ft from the muzzle and my 280Ack and 300Ack didn't bother it a bit - my Edge velocities were all over the place. I've got to get this corrected so I can see what my velocities really are. Next time I'm going to repeat these loads and move the chrono out to 25ft.

90 - no reading
90.5 - 2873 what???
91 - 2801 maybe?
91.5 - 2904 don't think so!
92 - 2783 uh - no

Again today brass looked like it took a beating. Below is a picture of the 90gr load showing heavy ejector mark and shiny area were the bolt face wiped it. Wish I had a better camera so you could see what I'm seeing.

You are spot on about needing to test accuracy at 200+ yards. The target below is typical of what I have been getting even when shooting different powder charges like I did today. This was shot at 108yds and target is oriented like I shot it. If it keeps shooting like this I'm just going live with it being a brass eater!

Maybe I got a soft batch of Nosler brass? I see Bertram brass in the near future!

Jay

 

[Broz]

Brass looks soft to me. But who knows. The face of the primer looks normally flat. But not excessive. Punch one out and see if it has straight sides or if it is muffin topped.

I will take that accuracy from a 338 especially a 5 shot group. 10-4 on the Bertram brass. You have the load and I bet it would only shoot better in fire formed Bertram EDGE brass.

Jeff

 

[nchunter182]

Jeff,
I have punched out several of the primers from the loads I just shot. I am seeing them slightly wider at the primer/bolt face than the middle of the primer by 3-4thou. The edge of the primer is still rounded.

 

[Broz]

Jeff,
I have punched out several of the primers from the loads I just shot. I am seeing them slightly wider at the primer/bolt face than the middle of the primer by 3-4thou. The edge of the primer is still rounded.

Well, I think you are concluding you could have some soft brass. Realize I do not want to lead you into a dangerous situation. So please be careful as I am not there to see the results in person nor should I make this call for you from a distance. But 3 to 4 thousands is not a "muffin topped" primer to me, especially if it has rounded corners. I have seen them from max loads that when rolled on the bench top turned a tight circle. I called those an over pressure load. I think all you need is a cool chamber and some lower fall temps with this brass. Go to 3 shot groups at 200 yards to check this load. If you notice a 3rd shot having a heavier bolt lift I would back off to 2 shot groups and do more of them at longer distances.

Jeff

 

[nchunter182]

Jeff,
That is what I'm concluding - I think the Nosler is just soft. No doubt this is a stout load though and caution will be taken. I'm not going to increase it any further but will do more testing to verify and back off if needed. Next time the chrono will be further out so I can verify my velocity readings.
Thanks for you feedback!

 

[RustyRick]

Correct me if I'm wrong, but I don't think COAL is as relevant as one might think. The shape of the bullet or ogive is what critical. The distance from bolt face to lands.

Different ogive seated at the same COAL will have different CBTO thereby camouflaging the results and causes. ???

 

[nchunter182]

Rusty,
You are correct. Different bullets of the same length (even same type or lot#) will have differing lengths when measured from the cartridge base to the ogive. I always set my seating die based on readings using the Hornady Overall Length Gage with the bullet I intend to shoot.
In this thread I've included the COAL just for reference. COAL does become very important when you are feeding through a magazine. My Edge has the Wyatt 4" box and I had the reamer built to allow me to take full advantage of this extra length.
Jay

 

[RustyRick]

OPh crap - I'm facing the same issue with a 660 Rem in a 6.5 Rem Mag. I'd like to kick the engineers butts that design a rifle with out facilitating a magazine that allows one to seat loads to the rifling instead of the magazine.