300RUM & Retumbo

Richracer1 · Nov 15, 2006

All you 300RUM loaders, what is MAX for Retumbo behind a 200gn AB. Hodgdon's site says 86 for a 200 gn Barnes bullet. I've searched and found POP's RUM likes 95gn, just curious. My 300RUM is the special run, thumbhole stock version, so I don't have the heavier Sendero barrel. Thanks. Still working on 180ABs, but since everyone seems to praise the 200AB, I decided to order some 200 2nds from the pro shop. Thanks for any info. Oh, I'm using Rem cases and Fed GM215M primers. Current COL is 3.635. I'll play with COL (or not) when I find a load that shoots well at this measurement.

Powerstroke · Nov 15, 2006

Richracer,
I can't be much help on the 200's. I've concentrated on the 180's and have those shooting great.
Length however, I'm sure you've noticed that the magazine will set your max length generally???
I do have a box of 200grn A.B's but havn't had good luck as of yet. ( again, not much time with them ) Good luck, and let me know.

RMiller · Nov 15, 2006

You would just have to work your loads up in your rifle.

My max for 200 grain bullets in my 300 rum is 96 That is as far as I went anyway. gave 3200 fps. If it is not max it is good enough for me.

The sierra manual shows 95.7 for a 200 SBT or matchking.

remingtonman_25_06 · Nov 15, 2006

My 300 RUM topped out about 96g as well. It shot great at 95g Retumbo though. Velocity was 3225fps out of 26" pipe. Start around 88-90g and you should be fine.

Richracer1 · Nov 18, 2006

Well, I now have to decide which powder to use, Retumbo or RL-22. Retumbo has a slight edge on accuracy, but with more recoil. Your guy's thoughts?

340boy · Nov 18, 2006

I am going to try Retumbo in my 300RUM for 200 grain bullets as well.
I don't know about RL22, I have had good luck with it in less overbore cartridges, have not tried it in any of the RUMS.

Richracer1 · Nov 18, 2006

Richracer1":23pni2ro said:
Well, I now have to decide which powder to use, Retumbo or RL-22. Retumbo has a slight edge on accuracy, but with more recoil. Your guy's thoughts?

Forgot to mention, this session was for the 180AB: deciding between
88.5gn of RL-22 or 98.5gn of Retumbo.

340boy · Nov 18, 2006

I would go with the Retumbo, yes, I know it will generate slightly more recoil, but you have already stated that the Retumbo load gives better accuracy. Also, I think that Retumbo might be more stable with regards to temperature extremes than is RL22.

remingtonman_25_06 · Nov 18, 2006

Richracer1 · Nov 19, 2006

Either way, I have plenty of powder as I purchased a 5lb tub of RL-22 and have an 8lb tub of Retumbo on the way. Figured I might as well get a big tub of Retumbo since I'll be working up loads for 200AB as well. The only thing left is to use up the factory ammo I bought to sight in the scope on some of these CA central coast hogs. Then start getting some long range target practice in with my reloads. Oh, what fun!!!!! :grin: