Hodgdon Retumbo 300 Win Mag

[Quicksilver338]

I would also try h1000. I'm running it in my 300wm with 215 bergers with good results. Essentially a powder charge is just a number. Back off a few grains and get a chronograph to shoot through. Your rifle is going to do what it likes...now whether the results are what you expected or not is up to the rifle. You have retumbo so start with that. If it doesn't work out h1000 would be the next best bet. Start low and work up, record plenty of data and pay attention to details.

 

[fmuguira]

I would be careful with Retumbo as I recall Hodgkin having some incorrect charge postings a number of years back. Memory is that they used some 300 WB loads and put on 300 WM.

Call Hodgkin tech direct and ask for help. I shot 78 grainsvwith a 208 AMax and it was a full power load!! With your heavier bullet I d think low to mid 70 grains might be top end!!

 

[bob4]

2nd/3rd on H-1000

 

[FURMAN]

Are you crimping? I have never had my hands on a 220 Sierra but those numbers should be fine with Retumbo. The SAAMI 300 WM has very little freebore but is set up different than most as it starts at like .315 then has the 1.5ish degree taper to the lands. It does not reach the lands for something like .3". The short freebore seems to confuse some. The 215 Berger can actually be seated pretty far out in a SAAMI 300WM chamber. I would do some more checking before I started switching bullets, primers, and powder. Retumbo works great in the 300. I prefer H1000 but retumbo works. The last time I used Retumbo in a WM it took 79 grains to equal my 76 grain load of H1000 with 215 Bergers.