338 Allen Xpress, RL33 load development

[Fiftydriver]

Those are some great results and really gets me looking forward to trying RL33 in my 300 AX with the same 230 gr Bergers.

As far as ES goes. I think there have been ALOT of good loads passed over simply because the ES numbers are a bit higher then most would want. I have never been one to get real hung up on extremely tight ES numbers. You hear guys bragging about their single digit ES and while its certainly not a bad thing to have very low ES numbers, in my experience, even at long range shooting and hunting, as long as your ES is under 40 fps, you can get extremely good results down range as your target at 700 yards clearly shows. I would say your ES had zero effect on your rifles accuracy at that range.

Have always found that if someone wants to tighten up their groups at long range, get a good scope level, USE IT!! And sort bullets by baring surface length. Have found this to have as much if not more effect on down range group size(vertical) then even bullet weight.

Again, I like to have ES in the 20s but I am alright with 30 fps and I have seen MANY 40 fps ES loads hold well under 1 moa at 1000 yards from field shooting positions. Other variables, such as shooting position and environmental conditions generally will have MUCH more effect on your down range group size then ES ever will.

To the extreme, I have a Ruger M77MkIIVT that I rebarreled to 22-6mm AI and twisted to shoot the 75-80 gr match bullets. Extreme spread is usually in the 60 fps range but that load will print 1/4 moa at 500 yards and has shot several 1/2 moa groups at 1/2 mile......

Again, I think a lot of GOOD loads have been passed up because their ES numbers were in the 30-40 fps range.

 

[MontanaRifleman]

I am a firm believer in putting faith in groups above numbers spit out from an imperfect measuring device. Where the bullets go after all is what is all about.

 

[Fiftydriver]

I am a firm believer in putting faith in groups above numbers spit out from an imperfect measuring device. Where the bullets go after all is what is all about.

Well said!

 

[clemens]

Is the step up in performance rl33 seems to bringing to the table only usable in large capacity magnums? Would magnums like 7rm-.300wm possibly benefit as well or is the cases to small? Same question for short magnums as well?

 

[Fiftydriver]

With very heavy bullets it may work well in the 7mm Rem Mag and 300 Win Mag but with standard weight bullets I would think it would be on the slow side and you would run out of capacity before pressures got up to where we really would want them.

Would be the same with the WSMs.

 

[branwill25]

Wow cool thread Kirby. I will have to try RL33. A local gun shop had some in stock and I have access to an 8 lb jug as well. I want to try the 300 RUM load usng the 230 bergers at 3200+. That sounds awesome! Have you guys seen a big improvement in the 338 Lapua as well? Thanks

Brandon

 

[TXAoudadKlr]

The 338AX being an improved version of the 338 lapua you should see roughly the same improvement's I'd imagine.

 

[clemens]

Thanks Kirby for the reply. This has been real informative thread

 

[AZShooter]

Thanks Kirby for sharing your information.

Clemens,

I think you can use RL-33 with a 7mm/300 win mag with the 180 Bergers and have good results.
RL-33 shines with the 7mm/375 Ruger and 180 bergers. The two have very similar case capacities.


I built two. One with a 29 3/8" barrel, the other with a 26" barrel.
Longer barrel uses 83 gr with 180 match target hybrid for velocity of 3200 fps.
Shorter barrel uses 84 gr with same bullet for velocity of 3070 fps.



My testing showed that there was no gain in velocity over H-1000 with the 168 gr classic Berger.

Data comparing 168 classic with RL-33 and H-1000 below. This was in my first barrel a used 24" 7 Rem Mag rechambered to 7mm/375 Ruger.

moly coated 168 classic H-1000:
78=3075 shoots very accurately
79=3090
80=3115
81=3135 also quite accurate
82 3205 vel jump/over the top/some bolt lift resistance

Moly coated 168 classic RL-33
85 3072
86 3093, 3080 not bad group size.
87 3148 some bolt lift resistance

If you have RL-33 give it a try with the 180s and the 7mm/300 win mag.

 

[Fiftydriver]

Wow cool thread Kirby. I will have to try RL33. A local gun shop had some in stock and I have access to an 8 lb jug as well. I want to try the 300 RUM load usng the 230 bergers at 3200+. That sounds awesome! Have you guys seen a big improvement in the 338 Lapua as well? Thanks

Brandon

It is ideal for the 338 Lapua. From what we are seeing, looks good with the 250 and 300 gr bullets. It may not show as much advantage with lighter weight 338 cal bullets but there are not many shooting lighter then the 250 for long range shooting anyway.

Very good in the big 30 cals also.

 

[MMERSS]

I loaded up a few rounds of RL-33 for pressure tests.

99gr of RL-33 is showing same velocity as 94gr Retumbo with the 300 SMK in my Lapua. There is some velocity increase with the RL-33 over Retumvo with the Bergers.

This makes me wonder if the improved cases are taking more advantage of the RL-33.

 

[MontanaRifleman]

Is the step up in performance rl33 seems to bringing to the table only usable in large capacity magnums? Would magnums like 7rm-.300wm possibly benefit as well or is the cases to small? Same question for short magnums as well?

It might work with the heavier bullets in the 7-300 WM but it is a slow powder, close to 50 BMG in burn rate. It is better suited for the more overbore cartridges. That said, the 7-300 WM is probably close to the 338 AX in overbore factor. Kirby would know better. I doubt it would work well in the 7 and 300 WSMs. Maybe in the 270 WSM. I think it will do well in the 6.5 WSM which I will be trying and it has already shown good results in the 6-284 which I also will be trying.

 

[MontanaRifleman]

I loaded up a few rounds of RL-33 for pressure tests.

99gr of RL-33 is showing same velocity as 94gr Retumbo with the 300 SMK in my Lapua. There is some velocity increase with the RL-33 over Retumvo with the Bergers.

This makes me wonder if the improved cases are taking more advantage of the RL-33.

Could be or maybe the improved version has enough extra capacity to take advantage of the slower burn rate. It's interesting that they advertise specifically for the 338 LM and secondarily for the large mags. It seems to work better in cartridges that are more over bore than the 338 LM.

 

[Outlaw6.0]

.... I think it will do well in the 6.5 WSM which I will be trying and it has already shown good results in the 6-284 which I also will be trying.

Good to know I was thinking the same thing with the 160's in the 6.5wsm... could be just the ticket? Not sure about the -284 with your 100's, you may have better luck with DTACS & RL-33 but don't let me sway you! I'm just as curious to see as you are


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