I bought four pounds when it first came out. I was told by Alliant it was a slower powder formulated like RL-17 which turns out not to be true. It also is NOT an extreme powder.
I recieved an e-mail from alliant about the temp. sensitivity of 4000 MR, They are calling it moderatly temp. sensitive...
Did some comparative testing. Was curious if 4000 MR would best RL-17's performance.
Two 7 Rem Mags were used. 24" and 30" barrels.
Original loads:
24" barrel. moly coated 150 nos bt, 67 gr of RL-17 vel 3260
30" barrel. Moly coated 140 accubond 66 gr of RL-17 vel 3400
Temperature for testing was mid 80s.
Worked up loads for 24" barrel, with two cases per 1 grain increments using same components/loading methods except for change in powder
66 gr vel 3046 3047
67 gr vel 3077 3106
68 gr vel 3151 3163
69 gr vel 3186 3183 max load for conditions
70 gr vel 3254 3264 hint of bolt lift/ shiny extractor mark
30" barrel again same components/loading methods
66 gr vel 3351 3287
67 gr vel 3356 3386
68 gr vel 3402 3403 hint of bolt lift bullets touched
69 gr vel 3452 3450 same bolt lift bullets touched
70 gr vel 3501 3477 accuracy fell off/harder bolt lift
71 gr vel 3521 3527 same as 70 gr
Impressions: this powder didn't surpass RL-17's velocities in the short barrel but duplicated and slightly surpassed RL-17 in the longer barrel. Some velocities were very similar as seen above. Has accuracy potential.
The extruded kernels are smaller, approx 1/2 the length of RL-17 with same diameter. Even with the max loads there is an air space between the powder and base of bullet.
I did a brief test with the 300 win mag:
300 win mag with 180 nosler pt, temperature 93 degrees
73 gr 3012 ave
74 gr sun angle messed with the chronograph, no velocities but two shots cut into one another
75 (suggested max load) 94 degrees, hard bolt lift, quit testing.
Sorry it wasn't much of a test. Too darn hot!
I eventually used most of this powder up in an old 30-06.
If I were to make a hunting load for a 300 win mag I would choose the 215 Berger match target hybrid and use H1000 as it does well with temperature changes, end of story. Read this thread and I am sure you will agree
again thanks to Broz for this thread)
https://www.longrangehunting.com/threads/comparing-the-berger-210-vld-to-the-215-hybrid.88657/page-6
