338 Rem Ultra 30" barrel loads-wanted

knc1105

Well-Known Member
Joined
Feb 22, 2010
Messages
224
I found a post online here from 8-9-2001 on 338 RUM loads and it was the best I have ever seen and I joined LRH. I have a new rifle coming day after tomorrow and it has a 30" Lilji heavy barrel and brake ( scaled down 3-chamber 50-BMG style brake ). All the data I have found is for a 26" barrel. The bullets I got to try first are Sierra 250 gr. GameKings and MatchKings and Hornady 250 gr Match (675 B.C.) I will have them Boran Nitate coated before I start. I have H4831, IMR4831, and H50BMG in stock, I am looking for 7828 also. I have Federal Large Rifle Magnum primers, I could not find any match primers. Any help would be greatly appreciated.
 
The powders best suited for those bullets are 7828, RL25, Retumbo and Ramshot Magnum. The 215 primers are fine, likewise the WMLR and CCI250.
 
I am told the longer barrel would not add chamber pressure, but would like the slower burning powders and have increased velocity with the slower powders. I got a e-mail from a 50 shooter that there was not enough case capacity for H50BMG and Retumbo was the slowest burning powder that I could use, those max loads were compressed loads. So I'll get some of the listed powders to start. I wonder if anybody has every loaded for a 30" RUM barrel, I can't be the first. The 30" is kind of the standard with the 50BMG and the Lapua shooters, maybe I screwed up. I got this for long range Elk hunting.
 
My stock M700LSS 338 RUM shoots well with Retumbo. With the Nosler 250 gr AB, this was the second target I shot with the load so I never bothered to try going up. Hodgdon web site says 101.0 grs is MAX.
338RUM250grABa-1.jpg

The same powder and charge weight with the Nosler 250 gr PT gave me an average of 3024 fps.

JD338
 
WOOOOOW! now thats the kind of secret recipe to try. My scope and rings came in Friday, all the reloading stuff that I did not have came in this afternoon and the rifle is scheduled for tomorrow. It's hard for a old hunter to not get exited like a kid. I probably won't sleep much tonight. Ain't it great!
 
Alot of my buddies call the 338 Ultra Mag a working mans Lapua, I always called it a Hunter's Lapua. The group posted above would make a bunch of S.W.A.T. teams jealous, and old Elk bulls shake in their hoofs.
 
This is a good load and not too hard on brass either. Same load from a clean barrel. Note the dark oil ring from the first shot.
338RUM250grAB412.jpg

Rifle is a stock 700 LSS with a Pachmayr Decelerator recoil pad and the trigger lightened to 2.5 lbs.
Scope is a Mark 4 4.5x14x40mm with M1 dials added.
700LSS338RUM.jpg

JD338
 
Now that is a bad*ss rifle, with the perfect hunting scope. Mine has a very similar laminated stock. I did not see a brake, is the recoil as bad as all the horror stories posted? Not meaning to sound like a big weenie, but I have a custom 3-chamber 50BMG style brake coming for mine that we'll put on Saturday. This is better than the Miculek we put on my ultra light 7mm and it kicks like a 223 bolt gun now.That rifle of yours shooting like that, with that bullet could shoot from one time zone to the next.
 
Has anybody tried or chronograhed the coated bullets? I have the powders and sent all my trial bullets to Superior Shooting Systems to be Boran Nitrate coated, I like it alot better than moly, it increases MV, reduces pressures and extends barrel life ALOT and does not have the negative humidity problems. On 223 and 308 you typically see 2-3 % 50-100 fps on this monster would be alot.
 
I have a 30 inch Broughton barrel on my 338RUM with a Muscle brake. Haven't shot it yet, I need to get some powder for 250gr. NAB either RL 25 or Retumbo, not sure yet.
Tarey
 
Your Muscle Brake ia ALOT better looking than mine, I have Miculek brakes on everything except the 338 RUM, it's recoil reputation preceeds it. I put on a 50BMG style brake that is scaled down in size, it is ugly unless you are a real tactical type guy, you can scroll down to the bottom of the website to see what I got @ boys50bmgatr.com they are custom made for each caliber and have progressive holes for each chamber and really work well. My gunsmith is bluing it to match the Lilji barrel a little better, but it still will not look as good as yours, sure wish I had known about yours.
 
No brake or porting. Recoil isn't too bad, even from prone. Rifle weighs 9 lbs.

JD338

Wow. That just goes to show recoil is a personal thing. That rifle calculates as having ~38+ ft-lbs if the all up weight is 11 lbs with scope. I've shot a .338 Lapua with a Holland bake - it feels about like my .30-06 (a 1953 M70 with blued steel butt plate). I can't imagine shooting that Lapua with out a brake. My ears already ring continuously - even with muffs on the brake is too much noise - I'd need muffs plus foam ear plugs and that would suck in the field.

I've found that around 25 ft-lbs (calculated) is my limit so I'm planning to build my .338 Win Mag to be 12.5 lbs all up with scope. I'd have to have a brake on a .338 RUM or have it weigh at least 17 lbs (more than this 68 year old 5'-7" 170 pound guy wants to carry around). That said, the .338 RUM sure looks like one fantastic cartridge. I wish there was such a thing as a quiet brake but there isn't, at least so far.

Fitch
 
I wear a set of foam ear plugs I found with a rating of 32db with a high end pair of electronic muffs, when I'm at the bench I turn them off and when I'm hunting I have been wearing them witout the plugs and can hear better than I can without them. We'll see if that is enough. I wear them whenever I'm shooting or hunting because I have a hearing loss and am trying to save what I have left, some will argue thats crazy but once you get used to it, it is a habit now.
 
Warning! This thread is more than 14 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top