Lets get some load data going for 338 Laupa Ackley Imp. Wouldn't mind hearing some. Going to re-barrel my 338 to this and see how fast I can get 300SMK going
338LM AI loads
- Thread starter Sonic Crack
- Start date
I have to say this. These loads worked in my rifle. Since they (rifles) are all different please start low & work up.
I had a 338 Lapua Improved that you could bet money on using a 300 gr. Sierra, Fed. 215M & 108.5 grs. Vit 24N41. This load averaged 3157 fps for 20 shots. We had an AR500 torso silhouette @ 1000 yards. With most cartridges it was hard to see the hits especially with mirage in a Georgia hay field. However when that 300 gr. SMK hit the silhouette I was rewarded with about a 2 ft. diameter grey cloud and pretty good clang. I used around the same charge weight of wc872 for getting on paper when changing scopes or come ups at different yardages.
While Vit. has discontinued 24N41 I have found that Alliant RL50 is extremely close. I now use RL50 in some 300 & 338 Norma Mag based wildcats I have come up with. I have some RL33 but have not tested it in the Norma Mag. based cartridges yet.
Semper Fi
I had a 338 Lapua Improved that you could bet money on using a 300 gr. Sierra, Fed. 215M & 108.5 grs. Vit 24N41. This load averaged 3157 fps for 20 shots. We had an AR500 torso silhouette @ 1000 yards. With most cartridges it was hard to see the hits especially with mirage in a Georgia hay field. However when that 300 gr. SMK hit the silhouette I was rewarded with about a 2 ft. diameter grey cloud and pretty good clang. I used around the same charge weight of wc872 for getting on paper when changing scopes or come ups at different yardages.
While Vit. has discontinued 24N41 I have found that Alliant RL50 is extremely close. I now use RL50 in some 300 & 338 Norma Mag based wildcats I have come up with. I have some RL33 but have not tested it in the Norma Mag. based cartridges yet.
Semper Fi
Got some brass fire formed. initial measurements show AI has 5.5 grains more water capacity
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Wow I thought I was gonna be smoking them at 106gr of rel33. But 108.5 grains is wicked. How was the pressure with that load?
no doubt 108 gr. RL-50 is pretty stunning. H2O capacity in my 338 LM Improved is 124 gr.
100 gr. Retumbo got me 2,950 fps w/ 300 smk;
100 gr. of VV570 got me 3,020 fps 300 smk
105.5 gr. RL-33 gets me 3,040 w/ 300 gr. Lapua Scenar. I did pressure testing up to 108 gr. (which got me to 3,100 fps), but stopped because I knew it would be over pressure in the vegas summer. RL-50 sounds like it might be worth considering.
Jeffvn
100 gr. Retumbo got me 2,950 fps w/ 300 smk;
100 gr. of VV570 got me 3,020 fps 300 smk
105.5 gr. RL-33 gets me 3,040 w/ 300 gr. Lapua Scenar. I did pressure testing up to 108 gr. (which got me to 3,100 fps), but stopped because I knew it would be over pressure in the vegas summer. RL-50 sounds like it might be worth considering.
Jeffvn
Fill capacity on 105.5 gr.
Its hard to say. My best guess from looking inside the case is 90-to-95%. (Capacity is roughly 124 gr. of H2O, and my pills are long-seated so the boat tail/bearing surface junction is above the shoulder/neck junction.)
108 gr did not compress upon seating (meaning go crunch), but I use a 6" drop tube funnel for everything so it gets consolidated into a much tighter package by the drop into the case. I have used loads that QL says will be compressed but using my 6" drop tube it does not feel like its actually compressing with the seating of the projectile.
JeffVN
Its hard to say. My best guess from looking inside the case is 90-to-95%. (Capacity is roughly 124 gr. of H2O, and my pills are long-seated so the boat tail/bearing surface junction is above the shoulder/neck junction.)
108 gr did not compress upon seating (meaning go crunch), but I use a 6" drop tube funnel for everything so it gets consolidated into a much tighter package by the drop into the case. I have used loads that QL says will be compressed but using my 6" drop tube it does not feel like its actually compressing with the seating of the projectile.
JeffVN
Fire forming I just used some cheap hornady 200 grain bullets and 83 grains of IMR4350. I punched out my old barrel and just shot up the rounds into the dirt. Most of the brass formed out good, some with shorter headspace will need fired again to get a good shoulder formed.
Did some pressure testing in my barrel. 29" 1-10 Bartlein, Melonited, 300 SMK.
H1000
92gr = 2755fps
96.5gr = 2873fps (heavy bolt lift, ejector marks)
Retumbo
94gr = 2751fps
103gr = 2980fps (HBL, EM)
H50BMG - huge kernels! started compressing powder @ 104gr
98gr = 2559fps
113gr = 2934fps (slight EM, very compressed, case fill a hair below NS junction)
Would like to try N570 & US 869. anyone have experience with their temp sensitivity? is it good or bad?
H1000
92gr = 2755fps
96.5gr = 2873fps (heavy bolt lift, ejector marks)
Retumbo
94gr = 2751fps
103gr = 2980fps (HBL, EM)
H50BMG - huge kernels! started compressing powder @ 104gr
98gr = 2559fps
113gr = 2934fps (slight EM, very compressed, case fill a hair below NS junction)
Would like to try N570 & US 869. anyone have experience with their temp sensitivity? is it good or bad?
