Loading parameters for 30-338

I just acquired a custom built 30-338 and am seeking information from those of you who have been loading and shooting this caliber wildcat as I can't find it in any reloading publications. I have been told to load it using the .308 Norma listed lowest loads and work up from there. I would like to see if some of you folks are familiar loading rounds for this caliber and save a little time and a bunch of money cutting to the quick without shooting a couple of hundred rounds.
Included with the trade were RCBS dies, 200 rounds of. 338 Win Mag brass and 190gr and 200 gr bullets. This rifle is made on a 1917 Winchester Mauser action, Shilen barrel and handmade wood stock. L&g's appear sharp and clean so I doubt it has been shot very much.
Anything anyone can give me advice regarding loads for this rifle and brass sizing will be greatly appreciated!

www.accuratereloading.com/30-338winmag.html.

I have a very similar rifle built on the same action but in .308 Norma Magnum. The action is actually an Enfeild design, not a Mauser. It was copied off a Mauser, but an Enfield nonetheless. I have another .308 Norma built on a Remington 700 action that I've done a lot of shooting with. The two cartridges are very very similar. I have tried IMR 7828, IMR 7977, RL23, and RL26 with 208gr Hornady ELDs. I also recommend starting at .308 Norma minimum loads and working up. Most of my loads I found on my own because there's no published data for the powders I use.

Jud96 said:

I have a very similar rifle built on the same action but in .308 Norma Magnum. The action is actually an Enfeild design, not a Mauser. It was copied off a Mauser, but an Enfield nonetheless. I have another .308 Norma built on a Remington 700 action that I've done a lot of shooting with. The two cartridges are very very similar. I have tried IMR 7828, IMR 7977, RL23, and RL26 with 208gr Hornady ELDs. I also recommend starting at .308 Norma minimum loads and working up. Most of my loads I found on my own because there's no published data for the powders I use.

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You're correct about the Enfield and the action taken from Mauser. I mentioned something about the Lennon Sisters the other day and no one knew who I was talking about so I try restraining chat about items older than they were. Thanks

H4831sc is where I would start looking. Depending on your actual chamber dimensions of your rifle, and barrel length you should end up around 3,000 FPS safely with 180 to 200g bullets and a 26" barrel. Beginning with 308 Norma loads is good advice and a safe place to start. 30-338 Win is more efficient though, in that it requires less powder to get the same velocity as 308norma. Especially so with 200g and heavier bullets. Watch your velocity closely as you work up.
Running the 185g berger juggernaut I found best accuracy with the lowest SD at 3,015 FPS from my 26" barrel. I'm three gains below where I encountered the first sign of a hesitation in bolt lift in my rifle.

Gone Ballistic said:

I just acquired a custom built 30-338 and am seeking information from those of you who have been loading and shooting this caliber wildcat as I can't find it in any reloading publications. I have been told to load it using the .308 Norma listed lowest loads and work up from there. I would like to see if some of you folks are familiar loading rounds for this caliber and save a little time and a bunch of money cutting to the quick without shooting a couple of hundred rounds.
Included with the trade were RCBS dies, 200 rounds of. 338 Win Mag brass and 190gr and 200 gr bullets. This rifle is made on a 1917 Winchester Mauser action, Shilen barrel and handmade wood stock. L&g's appear sharp and clean so I doubt it has been shot very much.
Anything anyone can give me advice regarding loads for this rifle and brass sizing will be greatly appreciated!

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Sierra manual # 5 has loading data for 30-338mag. I have 30-338mag build on Ruger #1 action and another 30-338mag on Rem 700 action. If you PM your address, I'll send you Sierra data. Sierra new manual # 6 has data for 30-338mag but don't have copy.

I've only used Sierra data.

Thanks so much for your advice and reply. I really appreciate it!

Gone Ballistic said:

I just acquired a custom built 30-338 and am seeking information from those of you who have been loading and shooting this caliber wildcat as I can't find it in any reloading publications. I have been told to load it using the .308 Norma listed lowest loads and work up from there. I would like to see if some of you folks are familiar loading rounds for this caliber and save a little time and a bunch of money cutting to the quick without shooting a couple of hundred rounds.
Included with the trade were RCBS dies, 200 rounds of. 338 Win Mag brass and 190gr and 200 gr bullets. This rifle is made on a 1917 Winchester Mauser action, Shilen barrel and handmade wood stock. L&g's appear sharp and clean so I doubt it has been shot very much.
Anything anyone can give me advice regarding loads for this rifle and brass sizing will be greatly appreciated!

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I've been shooting one since the mid 90's.
I struggled in the beginning finding a load as well until I loaded H-1000.
Now shooting 200 gr HPBT sub MOA with Dope to 1500 yards.
I put an Obermeyer barrel on Remington Sendero. I'm using form fired 7mm brass @ 2.50" COAL. CCI 250 primers, 70 gr. H-1000. It shoots sub MOA. With Sierra GK or MK, Hornady ELD, or Nosler Accubonds. It's a great Elk round as well as long range competition.

The 30-338 and the 308 Norma are really the same,the difference the Norma has a longer neck.I have a 308 Norma and have made brass for it necking up 7mag brass and necking down 338 Win Mag brass.The necks are a little short,but it didn't hurt anything since chambers are cut with a little extra room for the brass to grow a little.Your not going to find much load data using the modern powders unless you use the Quick Load data.I find the 308 Norma to be dang close to the 300 Win Mag.Mine has a 26" barrel and it probably is a very close rival to a 24" barreled 300 Win Mag.
Here is some QL data listed at max loads 63,250psi.It was worked up for my 26" barrel 308 Norma Mag with a 180gr Nosler Ballistic Tip.Some of the loads I've tried have run really close to this data.I have more powders,let me know if your looking for a particular one.
Reloader 26 77.1grs 3190fps
Reloader-22 74.5grs 3134fps
Magnum 80.0grs 3111fps
Reloader 17 68.1grs 3098fps
H4831 73.0grs 3068fps
H1000 77.6grs 3053fps
Win.760 68.2grs 3077fps
IMR7828 74.5grs 3134fps

baldhunter said:

3190fps
Reloader-22 74.5grs 3134fps

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Dam hot really cool round just squired one from cabellas grand junction col lol

Curious what kinda coal u was running I have win mag at3.4

Hotdiesel said:

Curious what kinda coal u was running I have win mag at3.4

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Sorry for being late getting back to you on your question,I was gone from home.My COAL on my 308 Norma Mag loads are 3.4"-3.45".My 300 Win Mag loads are 3.5" COAL.Here is the interesting part.
The 308 Norma Mag case length is 2.559
The 300 Win Mag case length is 2.620, .061" longer
The book COAL for the 300 Win Mag is 3.340"
The book COAL for the 308 Norma Mag is 3.346".That is .006 longer than the 300 Win Mag that has a case length that is .061" longer.Many 300 Win Mag rifles are built with mag boxes that are too short.A lot of the 300 Win Mags are 3.550" to the lands.The sweet spot for my 300 Win Mags COAL is right at 3.500".I have one 300 Win Mag that I have to shoot single shot because the bullets have to be seated so deep to function in the detachable magazine that the ogive of the bullet is already in the case neck and I can push the bullet in by hand.I wouldn't group at that short length either.I single shot one of my loads for my other 300 Win Mags that had a COAL of 3.50" and thi is how it did.

baldhunter said:

Sorry for being late getting back to you on your question,I was gone from home.My COAL on my 308 Norma Mag loads are 3.4"-3.45".My 300 Win Mag loads are 3.5" COAL.Here is the interesting part.
The 308 Norma Mag case length is 2.559
The 300 Win Mag case length is 2.620, .061" longer
The book COAL for the 300 Win Mag is 3.340"
The book COAL for the 308 Norma Mag is 3.346".That is .006 longer than the 300 Win Mag that has a case length that is .061" longer.Many 300 Win Mag rifles are built with mag boxes that are too short.A lot of the 300 Win Mags are 3.550" to the lands.The sweet spot for my 300 Win Mags COAL is right at 3.500".I have one 300 Win Mag that I have to shoot single shot because the bullets have to be seated so deep to function in the detachable magazine that the ogive of the bullet is already in the case neck and I can push the bullet in by hand.I wouldn't group at that short length either.I single shot one of my loads for my other 300 Win Mags that had a COAL of 3.50" and thi is how it did.

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Thanks a bunch I'm using 30/338 just curious best of luck

Hotdiesel said:

Thanks a bunch I'm using 30/338 just curious best of luck

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The 30-338 and the 308 Norma Mag as essentially the same cartridge.The only difference is the case neck is just a little longer on the Norma.You can use the same load data and COAL.I often use 7mag brass and neck up to 30cal,creating the 30/338 and shoot it in my Norma Mag.You can shoot a 30/338 in a Norma Mag,but you can't shoot a Norma Mag in a rifle chambered for a 30/338.My 26" barreled 308 Norma Mags produce about the same velocity as my 24" barreled 300 Win Mags,using a couple of grains less powder.