what velocity are you getting out of 338 lapua

[patross79]

guys i was wondering if you could help a new 338 lapua owner out. My set up is a Remmy 700 with the factory kick dirt and rocks in your face muzzlebreak. i worked up loads for it and settled on R19 with a 250 SGK powder charge is .3 grains under sierra's max for powder. 89.3 is max i believe without looking at the manual, i am at 89. anyway i chrony'd my reloads and sierra's estimates are at aprox 3000. i am getting 2875 give or take a few. do these figures seem correct? i was wanting to push em at 2950 + but the load is shooting great and i am not comfortable going over. So what are you guys geeting with your reloads. thanks.

 

[sniperjwt]

i say if its shooting great then leave it alone JMO

 

[Long Time Long Ranger]

My two 338 lapuas both shoot the 250 sierra gameking with best accuracy 3100-3150 fps. 7828, H-1000, Re 25 and Winchester WMR all do well. The most consistent and accurate loads were WMR but you can't get that anymore. 7828 is what I use most now. I think RE 19 is to fast for this round and the 250. RE 22 would be better. It is very close to the WMR I had good luch with.

 

[Kevin Thomas]

You made no mention of the barrel length involved here, and with the 338 LM, this can vary substantially between the various offerings. In our current (8th Edition) Reloading Guide, we ran the 250's up to 3,000 fps with N570. This was with a 700mm/27.5" barrel. Off the top of my head, I don't recall what we used at Sierra when the data was done, but it's worth taking a look and verifying if you're comparing top end velocities between manuals.

Kevin Thomas
Lapua USA

 

[Long Time Long Ranger]

Both of my lapuas are 26" barrels because the lapua case does very well in shorter barrels and I use these as light hunting rifles. With the lapua I saw on average about 15-20 fps per inch of barrel difference with most loads. I did quite a lot of testing with the lapua and improved version back in the 90's. My best load is 96.5 grains WMR at 3126 fps in my 26" barrel. Compared to my 340 wby with a 28" barrel my best load in it with 7828 powder is 3052 fps with less than 10 fps total velocity spread. My best load in my best 338-300 ultramag with the 250 gameking 3135 fps. Just not much difference in any of them.

Kevin, how much difference did you find per inch of barrel with the lapua? I was able to get over 3100 fps with the lapua and 250 grain bullet in all of them I have worked with. I probably run hotter loads than what companies allow to be published but were very safe in all the rifles I tetsed.

 

[Kevin Thomas]

LTLR,

I'm not the one who did the workups in the reloading data, for either the Sierra or Lapua manuals. I mention this simply because there is a tremendous amount to variation in the barrel lengths we're seeing in rifles chambered for the 338LM these days, particularly for those under consideration for the Precision Sniper Rifle contract fro SOCCOM. Seems to be a strong preference among some for very short barrels, which can make the 1,500m accuracy/energy requirements a bit tough. Hey, I can certainly apprecaite a lighter and handier rifle, but it's still gotta do the job once you get where you're going.

I used this cartridge as a standard accuracy round for my QC testing in the tunnel, and was always very impressed by it. There, I had the option of barrel length left to me, and generally ran 28-30" tubes on the various test rifles. Never had any reason to mess with anything shorter than that since (obviously) portability isn't an issue when dealing with a machine rest and barreled action. My concenr hre related more to those that have gotten ridiculously short, like some I've heard being pushed for the PSR competition. Once you start getting close to carbine lengths, you're giving up significant performance. That, and I sure don't wanna shoot it without double muffs and plugs, and someone else's shoulder against the butt!

Your velocities sound a bit high, maybe 100 fps or so compared to what we've seen in the manuals. However, as you've said, as long as it's not giving you any pressure signs and everything's functioning properly, you're probably fine.

Kevin Thomas
Lapua USA