New 338 NM Build and Load Work Up Advice

[JW74]

"JW74,
Do you neck-size after the first firing? If yes, does it show flattened primer still? Have you run a set of, Go No-Go and Field gauges in the rifle? I doubt that's the problem but you never know. My last thought(s), have you double-checked your scales? and do you live in a hot climate when you test your loads? Good luck, Cheer's

436, so far my loads have all been in new factory norma brass that has not been fired yet. My next step was going to be to full length size my once fired brass and see what kind of results I get. I believe my gunsmith used go no-go gauges in my rifle in the shop and all was good. I calibrate my scales before every loading session. I throw the charge with my electronic rcbs chargemaster and then double check on my beam scale before filling the case.

 

[JW74]

I use Retumbo with the 300 Bergers. Gets about 30 fps more than H1000 with the heavies. 89.9 grains @ 2780 fps from a 26" barrel. Can't find Retumbo any more so will try some IMR 8133.

H1000 and RE22 shot the 285 EDLMs about 25 to 30 fps more than Retumbo at 2850 fps. 88 grains of H1000

All loads are about 1/4" MOA from my gun.

jrock, those are the ballpark velocities I am hoping to get to. Great groups by the way! I also have some 285 grain ELDM's I am planning to load and try.

 

[jrock]

I should also add I've been having issues with H1000 lot consistencies with some powder cans I bought over the last several years. I threw out one pound that was obviously too slow, like 100 fps slow. Of course this was powder probably purchased 2 years ago. Never before have I had any issues with lot consistencies. I ordered an 8 lb keg to avoid this in the future.

 

[436]

436, so far my loads have all been in new factory norma brass that has not been fired yet. My next step was going to be to full length size my once fired brass and see what kind of results I get. I believe my gunsmith used go no-go gauges in my rifle in the shop and all was good. I calibrate my scales before every loading session. I throw the charge with my electronic rcbs chargemaster and then double check on my beam scale before filling the case.

JW74,
You might want to go right to the neck size only first, just bump the shoulder enough so that the cartridge has just a slight press fit on the bolt going into battery then you'll know that it's dimensionally correct with your chamber and headspace. Back off a touch more on your bullet jump to start with. I would still have a smith run a field gauge in it as well. I also use an RCBS Chargemaster and I use the Ohause 311-00 Cent-O-Gram overhead mechanical balance, 311g X 0.01 to check it periodically, you might take your Chargemaster scaling part off then hold it upside down and blow, "very softly" a little air over the port that the balance pan goes into just in case you have a few flakes or grains in it near the balance mechanism, I've only had to do that once because of some small faulty readings off and on, it works'.., it has thrown charges spot on every since. Cheer's

 

[fisherman987]

I just had a 338 Norma magnum built and am in the early phases of my load work for it. If others here that have loaded for the 338 NM could give some feedback it would be greatly appreciated.

The rifle is built on a Defiance Deviant action with a Bartlien barrel (27" heavy varmint contour @ 1:9.3" twist).

I went with 300 grain Berger bullets to start and H1000 powder as this seems to be a very common combo in the 87-88 grain range at 2700+ fps. I started very conservatively, and the loads and velocities are as follows:

300 grain Berger Hybrid OTM
H1000
Fed 215M
New un-fired Norma brass
2.836" to ogive (0.018" jump)

1) 81.0 gn @ 2584 fps
2) 81.5 gn @ 2595 fps
3) 81.8 gn @ 2618 fps
New Lot of powder used (velocities dropped)
4) 82.1 gn 2540 fps
5) 82.5 gn 2590 fps
6) 82.8 gn @ 2585 fps
7) 83.1 gn @ 2610 fps
8) 83.4 gn @ 2620 fps
9) 83.7 gn @ 2627 fps
10) 84.1 gn @ 2630 fps

This was over a couple of range sessions. I am still ~4 grains and 100 fps below what most people are getting with H1000 and I am starting to see signs of pressure with flatish looking primers, no cratering of the primers though and no stiff bolt lift yet. All of these groups were close to 1/2" at 100 yards with SD's from 4-12. I still have a little room to go up in charge but don't think I will get close to 87-88 grains without high pressure. I am wondering if I may have a tight barrel and that is why I am seeing pressure earlier than most?

I also tried the same loads but substituted Reloader 33 for H1000.

300 grain Berger Hybrid OTM
Reloader 33
Fed 215M
New un-fired Norma brass
2.836" to ogive (0.018" jump)

Those loads were:

1) 91.0 gn 2559 fps
2) 91.5 gn 2574 fps
3) 92.0 gn @ 2601 fps
4) 92.5 gn @ 2610 fps
5) 93.0 gn @ 2642 fps

The Reloader 33 produced these velocities with no real signs of pressure but the groups were not as promising as with H1000 and the SD's averaged higher at 15-20.

Thanks for any feedback or advice on these loads and further load development as it is greatly appreciated.

I think you have tried two of the best powders. I have had the best success with RL 33. I would keep exploring higher velocities with the RL 33 up to around 2800 fps range as long as you don't hit pressure issues as that has been a consistent velocity node for me using same brand and length of barrel, same action, same twist as you. Also using jump of. 020

 

[Swinehunt74]

I have one of the first 338NM made. Load development originally started with Magnum and R22 powders. Both work great behind 300gr bullets. I have stuck with SMK's with R22 with 82-84grs with 82.5 for accuracy and velocity at 2775. Shot out to Mile and half and ran out of scope (NF NXS 5.5-22). Pics are results from mile 300SMK. second pic was first two shots on upper right corner of frame, check out impact on girder at a mile. Follow up shot with correction in elevation just to right of center.After repainting target bnext 6 shots were as follows, 2 lower left blk, next two in pink on left, with last 2 shots in yellow. Disreguard middle hole, it was in boiler plate already. Had to dial in over 6mils of windage, shot on ranch in panhandle of Texas. last pic is looking back at shooting position from mile away.

 

[Mike 338]

New unfired Norma brass. Thanks for reminding me about brass brand. I also edited my post above to include that.

I had a 338 Norma that was giving me fits with early pressure signs. I finally gave up on it and rebarreled it to something else. Looking back, I suspect it was the brass but Norma was the only one with the brass at the time. Were it me, I'd try a different brand of brass. Maybe contact Lapua as it was suppose to be available a long time ago.

 

[JW74]

I think you have tried two of the best powders. I have had the best success with RL 33. I would keep exploring higher velocities with the RL 33 up to around 2800 fps range as long as you don't hit pressure issues as that has been a consistent velocity node for me using same brand and length of barrel, same action, same twist as you. Also using jump of. 020

Thanks for the info! I plan to continue working up loads with the RL33 this week. What kind of accuracy did you ultimately end up seeing?

 

[JW74]

I had a 338 Norma that was giving me fits with early pressure signs. I finally gave up on it and rebarreled it to something else. Looking back, I suspect it was the brass but Norma was the only one with the brass at the time. Were it me, I'd try a different brand of brass. Maybe contact Lapua as it was suppose to be available a long time ago.

I plan to try either some Lapua brass if it comes back in stock or Peterson brass as I have heard good things about it as well.

 

[JW74]

I went out yesterday and worked up some more loads. Still working with new un-fired brass at this point and plan to pick up some Peterson brass shorty if available. Based of of my velocities I do think I have a tight barrel that is causing higher velocities and pressure at lower charge weight than most others have been reporting.

300 grain Berger Hybrid OTM
H1000
Fed 215M
New un-fired Norma brass
2.836" to ogive (0.018" jump)

1) 85.6 gn @ 2703 fps
2) 85.9 gn @ 2727 fps (stiff bolt - stopped here with H1000)

300 grain Berger Hybrid OTM
Reloader 33
Fed 215M
New un-fired Norma brass
2.836" to ogive (0.018" jump)

Those loads were:

1) 95.5 gn @ 2750 fps
2) 95.9 gn @ 2776 fps
3) 96.3 gn @ 2779 fps
4) 96.7 gn @ 2805 fps
5) 97.1 gn @ 2839 fps

No real pressure signs with the Reloader 33 other than the flat primers as mentioned before. The velocity with the RL-33 is great but the accuracy and SD's are better with the H1000. I will try some of these loads with once fired brass and also with Peterson and/or Lapua brass and see what happens. For now I may settle on 85.6 gn of H1000 @ ~2700 fps and begin working on loads with the Hornady 285grain ELD.

 

[JW74]

I am about to head to the range for some more load development work this week and was wondering if anyone has had any success using RL26 with 285-300gn bullets in their 338NM? I have some RL26 and thought I would give it a try. I tried RL33 and Berger 300gn bullets and the velocity was great but the SD's were a little high and the groups were not as good as I saw with H1000.

 

[codyadams]

I used RL26 with with 265 ABLR's, there is a fair bit of info on this thread -

338 Norma Reloading Data

i just pick up a new Christensen Arms in a 338 Norma and I am having a hard time finding reloading data. I did call Berger and they were king enough to email me some data but I am looking for so pet loads to start. Any input would be great. It is a 1 in 9 twist barrel.

www.longrangehunting.com

Page 6 I list data with H1000, RL26, and IMR7828SSC and the 265. I also loaded H1000 in the 285 Hammer Hunter as well, look at that data and compare my info to yours, and should get you in a good ballpark range. Keep in mind my rig is a 24" barrel.

 

[sp6x6]

I have 2 normas pretty much same load as jrock.Went up to 90 gr,but settled at 87.5 for 2750,out of 26''My rifle ten years old Defiance.Ive shot one box ten times and retired that brass,Norma.300 otm,I have 6-8 lbs retumbo.Im going try 240 superdozier when I have time,mine 1:10 Good shooting ranger

 

[JW74]

I used RL26 with with 265 ABLR's, there is a fair bit of info on this thread -

338 Norma Reloading Data

i just pick up a new Christensen Arms in a 338 Norma and I am having a hard time finding reloading data. I did call Berger and they were king enough to email me some data but I am looking for so pet loads to start. Any input would be great. It is a 1 in 9 twist barrel.

www.longrangehunting.com

Page 6 I list data with H1000, RL26, and IMR7828SSC and the 265. I also loaded H1000 in the 285 Hammer Hunter as well, look at that data and compare my info to yours, and should get you in a good ballpark range. Keep in mind my rig is a 24" barrel.

Thanks Cody. I read over the thread and have made some notes. I'll post my results as I move ahead.