IMR 8133 for Cheytac 375

[justbill]

I was reading an old thread about substitute powders for Retumbo. One member asked the question: Has anyone tried using IMR 8133 for 375 Cheytac loads? Did not see any answers, so I would like to ask the question once more. Anyone using IMR 8133 to load 375 Cheytac?

 

[ohsmily]

Bumping this to see if anyone has a substantive response. Inquiring minds want to know due to the absolute unavailability of Retumbo.

 

[oinco]

up top... have some inbound...starting load suggestion? I am guessing 1gr off of Retumbo?

 

[Dogtown]

What bullet are you shooting?

IMR 8133 should be pretty good in a .375CT, from what QL is telling me.

I used the Cutting Edge 352gr because it was a very common bullet for .375CT. I have no experience with the IMR 8133, but according to burn rate charts, it's similar to Retumbo, RL33, and N570.

Now take this all with a little more than a grain of salt, but using QL for an educated guess, I'd say you're probably safe (using the above specs) from 129gr to 136gr.

 

[justbill]

Thanks Dogtown. I was planning on using Cutting Edge 352gr to start experimenting with the load. I will give 8133 a try, perhaps starting around 125gr for a few rounds just to check pressures.

 

[GIXXER2000]

I run N570 at 131.5 with 400 CE Lazer bullet AVG FPS 3060/ sd 6.5 in a 34 in 1-7 twist barrel. Never tried 8133 but have shot with guys using H -BMG 50.

 

[Flywheel]

There's some BMG50 and RL 33 near me. If you're looking for it. I'm sure we could work something out

 

[oinco]

Thanks Dogtown, running 377 MTACS for sure, and considering the 353 Lehigh and/or 361 FL.
BMG seems to get the top speeds at the cost of throat wear? 8133 and 20N29 seem like much cooler burning powders according to QL?

 

[Sleepertruckguy]

I run N570 at 131.5 with 400 CE Lazer bullet AVG FPS 3060/ sd 6.5 in a 34 in 1-7 twist barrel. Never tried 8133 but have shot with guys using H -BMG 50.

How far off the lands are you seating your bullet?

 

[GIXXER2000]

I load 5 off... tried 10 and 15 but the CE bullets seem to like being just off the lands the best.

 

[Sleepertruckguy]

Berger 407g
N570 - 131.5g
Avg speed 2,943 FPS.
SD 5.5
EXCELLENT GROUPING (1/4 moa)