New to .338 Lapua reloading

[Roblonsberry]

I am purchasing my first long range setup in 338 Lapua.
I have some experience reloading but not with a large caliber.
I have H4350 for 250 grain bullets. Problem is I can’t get my hands on magnum primers up here in Canada. I have large rifle CCI though.
Since I use these on my 6.5 creedmoor with 41.5 grains of h4350, will it be ok to use on the 338 since the powder weight is nearly doubled?
I’d love to use Retumbo or h1000 but it’s impossible to find here. Hours searching online with no luck. I spent a whole day driving to ma and pa type gun stores to no avail.

 

[RegionRat]

https://www.snipershide.com/shooting/threads/338-lapua-magnum-primers.108533/

 

[ShootnFool8]

Ramshot Magnum, Ramshot LRT, Reloader 33 are just some others that might work for you.

 

[Vivacious Stallion]

Unless you have found some trusted literature giving you info on how much of that powder to use, I would stay away from using 4350 for that. How were you going to judge a safe starting load???

 

[6.5SH]

You can't just double a charge for another cartridge and expect it to work.
The max on a fast for that cartridge powder is going to be well under what you think and will give poor results due to a less than optimal fill rate.

Look at the widely available load data then try to find something closer to the burn rate you need. Any of the 4350 range powders ain't it.

 

[Dogtown]

Ramshot LRT will be the easiest to find, but it’s slow in that cartridge.

For 250s, here are some good powder options...

And if you were wondering why using H4350 would be a bad idea?

It's a best practice to keep your Fill Percentage somewhere in the 90s. You can do the 80s, but it starts to get a bit iffy and DO NOT GO INTO THE 70s because that can lead to a detonation (all powder burns at once vs linearly from the primer to the neck).

If you're shooting 250s in an average .338LM barrel length (26-28") you should be easily in the 2850-2950fps range. With H4350 you're really only safe in a slim window of charges. In Kurdish we'd say that's "Nah bash!"

 

[Roblonsberry]

Thanks everyone.

 

[Roblonsberry]

Ramshot Magnum, Ramshot LRT, Reloader 33 are just some others that might work for you.

Found some RamShot magnum Thanks

 

[ShootnFool8]

Found some RamShot magnum Thanks

What grain bullet did you settle on. I saw 250 up top, but not sure, if you changed.

 

[Roblonsberry]

I haven’t settled yet. The firearm is going to take a lot longer than I was quoted.
Going to be well into next year before I get to start testing.

 

[Alaska]

H1000 @ 91.0
300gr Berger Tact
Fed 215M
Lapua Brass

 

[Dave62677]

RL26 86gr will get you 2900ish with 250gr pills.

 

[Roblonsberry]

H1000 @ 91.0
300gr Berger Tact
Fed 215M
Lapua Brass

Can’t wait to get the rifle and try this recipe out. I actually have these same components

 

[Roblonsberry]

RL26 86gr will get you 2900ish with 250gr pills.

I haven’t seen any RL26 but will try this if I can get some. Thanks

 

[Kazman1960]

I haven’t seen any RL26 but will try this if I can get some. Thanks

Not sure if you have access to this powder , IMR4831 . Thats my go to powder for my .338 Lapua .
In fact , this is my goto for most of my Magnum loads as well as a load in my 6.5 Creedmoor that my Remington tends to favor .

 

[Roblonsberry]

Not sure if you have access to this powder , IMR4831 . Thats my go to powder for my .338 Lapua .
In fact , this is my goto for most of my Magnum loads as well as a load in my 6.5 Creedmoor that my Remington tends to favor .

I’ll have a look. Just picking some h1000 up tomorrow

 

[Alaska]

In a big magnum Lapua H1000
H1000 @ 91.0 to 92.0
300gr Berger tactical
Lapua Case and Fed 215M primers

 

[Roblonsberry]

Ironic I just got it out it to test. Was having issues with my chrono mount but it seemed to have a node around 91. No pressure signs either.
going to make up another batch and try again next weekend.

 

[Kazman1960]

Ironic I just got it out it to test. Was having issues with my chrono mount but it seemed to have a node around 91. No pressure signs either.
going to make up another batch and try again next weekend.

What powder , bullets were you using ?

 

[Roblonsberry]

H1000, eldm 285, CCI mag large rifle primers, Lapua brass

 

[Kazman1960]

H1000, eldm 285, CCI mag large rifle primers, Lapua brass

Be sure to let us know how that combo performed . I just happened to stumble on what seems to be the best load in my rifle .

 

[Roblonsberry]

I will when I get the bugs in my chrono figured out. My mount kelts loosening so I missed a fair bit of data. Seems to be a node around 88.2 and 90.2 Groups were slightly sub MOA

 

[Alaska]

Ironic I just got it out it to test. Was having issues with my chrono mount but it seemed to have a node around 91. No pressure signs either.
going to make up another batch and try again next weekend.

300gr Berger OTM Tactical

 

[Roblonsberry]

300gr Berger OTM Tactical

Been looking for them

 

[ChrisGarrett]

For the 250s in my 1:12” twist TRG-42, VV165 and H-4831sc are my go-to powders, going on 17 years.

H1000 has performed well.

Chris

 

[Rbxbear44]

New to the Forum and precision shooting. Been reloading my 300 win mag, 270 win, 308 hunting loads for many years. Bought a 338 LM Ruger Precision a few years ago, created a great load for it. Bought a Christensen Arms MPR 338 LM about a year ago, still working on loads for it. Using a Berger OTM Tactical 250, H1000, Fed 215 Primer, Lapua Brass on both guns.

Not so happy with CA MPR. Feeling like now, I am chasing loads rather than finding one! Bipod only, no beanbag rest for stock.

Being a "rookie" at this load and caliber, I am seeing some trends from these posts...the gun runs more accurate on a 300 Gr bullet with H1000. Is this correct? Also, according to Nosler Reloading data, H1000 mid point is 92.0. I started both guns at 91.0, and worked up slowly to 93.0, then settled the Ruger Precison load at 92.8. BUT, having inconsistency with CA MPR at 93.0.

Ran five shot groups side by side with both guns. Ruger is bottom target. CA MPR is Top. 100 Yard Target, Right quartering headwind at 12-15, 58 degrees temp, fairly high humidity.

I did run another 5 shot group for each gun...Ruger stayed tight while MPR got worse, almost shotgun spray, stayed inside the target but went high then left on the last two rounds.

HELPFUL thoughts???
Thx

 

[Roblonsberry]

New to the Forum and precision shooting. Been reloading my 300 win mag, 270 win, 308 hunting loads for many years. Bought a 338 LM Ruger Precision a few years ago, created a great load for it. Bought a Christensen Arms MPR 338 LM about a year ago, still working on loads for it. Using a Berger OTM Tactical 250, H1000, Fed 215 Primer, Lapua Brass on both guns.

Not so happy with CA MPR. Feeling like now, I am chasing loads rather than finding one! Bipod only, no beanbag rest for stock.

Being a "rookie" at this load and caliber, I am seeing some trends from these posts...the gun runs more accurate on a 300 Gr bullet with H1000. Is this correct? Also, according to Nosler Reloading data, H1000 mid point is 92.0. I started both guns at 91.0, and worked up slowly to 93.0, then settled the Ruger Precison load at 92.8. BUT, having inconsistency with CA MPR at 93.0.

Ran five shot groups side by side with both guns. Ruger is bottom target. CA MPR is Top. 100 Yard Target, Right quartering headwind at 12-15, 58 degrees temp, fairly high humidity.

I did run another 5 shot group for each gun...Ruger stayed tight while MPR got worse, almost shotgun spray, stayed inside the target but went high then left on the last two rounds.

HELPFUL thoughts???
Thx

View attachment 8034527View attachment 8034529

I too had problems finding a load. It’s my first magnum to reload. Many people have told me that magnums can yaw within 2-300 yards. That didn’t make sense to me. When it tested Eldm my groups were the same size from 100 to 200 yards. I’d never believed it till I saw it. at 100 they were just under MOA.

One of the mistakes I made was underestimating the recoil blast. It was moving my magnetospeed mount! It ended up skewing the data since it was coming into contact with the brake. I’m not sure when it happened but surely that had an effect.

I highly suggest using more support just to take the human error out of it.

After going through about 100 test loads I found one mine liked. I use Lapua brass, 250 grain scenars, CCI 250 primers and a load of H1000. 3150 fps. Since the modified case I got isn’t close to fitting my chamber there no point in giving you the base or ogive measurement but it’s is very close to the lands. I‘m going to try the OTM when I can get some up here.

 

[Rbxbear44]

I too had problems finding a load. It’s my first magnum to reload. Many people have told me that magnums can yaw within 2-300 yards. That didn’t make sense to me. When it tested Eldm my groups were the same size from 100 to 200 yards. I’d never believed it till I saw it. at 100 they were just under MOA.

One of the mistakes I made was underestimating the recoil blast. It was moving my magnetospeed mount! It ended up skewing the data since it was coming into contact with the brake. I’m not sure when it happened but surely that had an effect.

I highly suggest using more support just to take the human error out of it.

After going through about 100 test loads I found one mine liked. I use Lapua brass, 250 grain scenars, CCI 250 primers and a load of H1000. 3150 fps. Since the modified case I got isn’t close to fitting my chamber there no point in giving you the base or ogive measurement but it’s is very close to the lands. I‘m going to try the OTM when I can get some up here.

Good intel! Yes, you are right on the support...should have done that since I am still in the hunt for a load on this gun. I'll run them again with more secure bench rest and see how that might clean things up a bit. I've moved all my hunting rifles to Weatherby 300 Weatherby Mag, 338-378 and 30-378, so my mind has been imprinted with faster is better!!! BUT, I give into those that know this much better than me.

I do have a chrono...still in the box from two years ago LOL...I'll break it out too.

Thank you!

 

[babyguppy]

I am purchasing my first long range setup in 338 Lapua.
I have some experience reloading but not with a large caliber.
I have H4350 for 250 grain bullets. Problem is I can’t get my hands on magnum primers up here in Canada. I have large rifle CCI though.
Since I use these on my 6.5 creedmoor with 41.5 grains of h4350, will it be ok to use on the 338 since the powder weight is nearly doubled?
I’d love to use Retumbo or h1000 but it’s impossible to find here. Hours searching online with no luck. I spent a whole day driving to ma and pa type gun stores to no avail.

start here

338 Lapua Magnum

pyrofx XSergeant Rating: 3.0/5 this site 388 posts this site >338 Lapua Magnum 10/08/2014 (1 vote) Just tried the reloader 33 powder in the 338 . 99.0 gr Kreiger 9.3 x27 fed 215mag hornydaddy 285 2789 es of 6 with hornydaddy brass. bolt lifts fine untill the cam over . then it takes a bit of...

www.snipershide.com

TONS of good info, this will do 98% of your legwork

 

[Dogtown]

Something I’ve noticed over the years with folks moving up to the big magnums for the first time: you might be flinching. Some people handle the significant increase in recoil well, while others need some work. For the latter, this can result in being able to bang steel just fine at a thousand yards but can’t keep hundred yard groups below two MOA. And you have to be a little more diligent about checking the torque on your scope mounts over time.

 

[babyguppy]

Something I’ve noticed over the years with folks moving up to the big magnums for the first time: you might be flinching. Some people handle the significant increase in recoil well, while others need some work. For the latter, this can result in being able to bang steel just fine at a thousand yards but can’t keep hundred yard groups below two MOA. And you have to be a little more diligent about checking the torque on your scope mounts over time.

I added Blue Loctite to all the tiny pieces on my scope + mounts; since I don't plan on taking it off in the next 5 or 10 years
>>.like you said Dogtown.. I had one come loose, and after large amounts of frustration, realized it wasn't me.

 

[Rbxbear44]

Something I’ve noticed over the years with folks moving up to the big magnums for the first time: you might be flinching. Some people handle the significant increase in recoil well, while others need some work. For the latter, this can result in being able to bang steel just fine at a thousand yards but can’t keep hundred yard groups below two MOA. And you have to be a little more diligent about checking the torque on your scope mounts over time.

I run a Barrett 50 cal, 338-378 too, mostly on paper targets. I have no fear of recoil or compression. BUT, you are right. I am self taught, and being an avid Big Game hunter for over 40 years, it's always been "aim small, miss small" for me. So, I am teachable. I will run the next session of rounds in a full cradle I use for zero'ing newly mounted scopes. Will see how it goes.

Enjoying reading through these threads. Appreciate all the wisdom.

 

[Rbxbear44]

start here

338 Lapua Magnum

pyrofx XSergeant Rating: 3.0/5 this site 388 posts this site >338 Lapua Magnum 10/08/2014 (1 vote) Just tried the reloader 33 powder in the 338 . 99.0 gr Kreiger 9.3 x27 fed 215mag hornydaddy 285 2789 es of 6 with hornydaddy brass. bolt lifts fine untill the cam over . then it takes a bit of...

www.snipershide.com

TONS of good info, this will do 98% of your legwork

Just read through...great stuff for sure. I am going to try a few things...

Go with BiPod AND bean bag set up for bench shooting.
Load some 4831SC at 88.0, 88.2 and 88.4 to compare with H1000 and Berge3 250 OTM Tacticals
I think I might be over charging my H1000 and these Berger 250's. Berger says 90.0 max and I am running at 93.0 (Nosler Reloading Manual). Although, No sign of over pressure at all.

 

[babyguppy]

Just read through...great stuff for sure. I am going to try a few things...

Go with BiPod AND bean bag set up for bench shooting.
Load some 4831SC at 88.0, 88.2 and 88.4 to compare with H1000 and Berge3 250 OTM Tacticals
I think I might be over charging my H1000 and these Berger 250's. Berger says 90.0 max and I am running at 93.0 (Nosler Reloading Manual). Although, No sign of over pressure at all.

Sierra Manual Edition 5 , 8th printing has
250 grains , H1000 Max load as 100 grains for 3,000 fps. Sierra was using their 250 grain bullet
FYI - I found Berger to be on the conservative side and Sierra to be 100% honest. If Serria says, don't do it.. I do NOT do it.
*Disclaimer - please be aware of pressure signs and all that stuff.
Sierra used a 26" barrel, 1X10 twist, and 93.6 grains of H1000 was around 2850 FPS

 

[Kazman1960]

New to the Forum and precision shooting. Been reloading my 300 win mag, 270 win, 308 hunting loads for many years. Bought a 338 LM Ruger Precision a few years ago, created a great load for it. Bought a Christensen Arms MPR 338 LM about a year ago, still working on loads for it. Using a Berger OTM Tactical 250, H1000, Fed 215 Primer, Lapua Brass on both guns.

Not so happy with CA MPR. Feeling like now, I am chasing loads rather than finding one! Bipod only, no beanbag rest for stock.

Being a "rookie" at this load and caliber, I am seeing some trends from these posts...the gun runs more accurate on a 300 Gr bullet with H1000. Is this correct? Also, according to Nosler Reloading data, H1000 mid point is 92.0. I started both guns at 91.0, and worked up slowly to 93.0, then settled the Ruger Precison load at 92.8. BUT, having inconsistency with CA MPR at 93.0.

Ran five shot groups side by side with both guns. Ruger is bottom target. CA MPR is Top. 100 Yard Target, Right quartering headwind at 12-15, 58 degrees temp, fairly high humidity.

I did run another 5 shot group for each gun...Ruger stayed tight while MPR got worse, almost shotgun spray, stayed inside the target but went high then left on the last two rounds.

HELPFUL thoughts???
Thx

View attachment 8034527View attachment 8034529

Mine loves the IMR 4831 and 250g Scenars .

 

[RegionRat]

When doing load development for magnums from the bench, I would work with both front and rear rests and wear my highpower "Hardback" coat.
You will last longer and you are less likely to become part of a questionable shot.

Happy New Year!

​

 

[Alaska]

I like to hunt
Had a 2 338 Lapua a Rem 700 and a AR-30
Both extremely accurate especially the AR-30.
H1000 at 91.0 with 300gr Berger was my load in Lapua brass.
I eventually sold both after I bought a Rem 700 XCR2 in 338 RUM. I quickly had it magnaported and a HS stock and detachable magazine installed. I only shoot 225gr Swift A frame or Nosler Part with 91.0 of RL 22. Much lighter to carry than the Lapua.