300 RUM and Retumbo

[Overkill338]

Since we are having some beautiful weather, I'm going to play around with some 200gr Gamekings tomorrow. I'm loading up a ladder between 93 and 95gr in 1/2gr jumps. Going to test them at 3.600". Does that sound about normal for Retumbo and 200gr bullets ?

 

[trueblue]

Quikload tells me 95.9 gr Retumbo puts you at max pressure loaded at least 0.020 off the lands, If you are loding on the lands 90gr is the max.

Standard release :This information is provided for your convenience. It is your responsibilty to work your loads up and watch your pressure.

 

[MontanaRifleman]

I was able to get 96 gr of Retumbo behind 200 AB's @ about .020 off the lands. 96.5 sometimes showed some slight signs of pressure. My chrony readings were a littel sketchy, but about 3200 fps or so is what I think I was getting. I ran out of 200 AB's and went with my 180 E-Tip load, so I didn't pursue any more development with the 200's.

Rem brass and Fed GM215M

 

[elkaholic]

I was getting 3300'+ with 95 grs. and a 200 AB in a 30" barrel. This was in an 11 twist barrel and 96 grs. was about max. Accuracy was good at 95 grs.........Rich

 

[Iron Worker]

I have loaded 95grs of Retumbo behind 200 AB out of 26" bbl and it produced 3200 FPS with excellent accuracy .

 

[dustybrown]

I have shot 500 rounds of 185 bergers and my throught must me going. I switched to 190s and it came back. group shrunk back down. If you find an accurate load before the max it might be the one to use. I was also told that as a BBL seasons it may change what it likes. In my rifle 3.680 has shot the best for me. 3.80 is jamed with 185`s going to try 210`s this week end. I had no preasure signs with 96.0 gr retumbo and 185,s ... seem like im starting over again. 190 sierra hpbt match shoot the best but im afraid to use them on game.

 

[KDB]

I ran a ladder test a few weeks ago at 1K using Retumbo and 208 Amax's. My chronograph was reading unreliably so I don't know the velocities, but I started at 94g of Retumbo and ran it 96.5g in .5g increments. Bullet was lightly jammed in the lands.

95 grains was my best 5 shot group. Very little vertical spread and 4 of the 5 shots were inside 5 inches. Under corrected for the wind on one shot that blew my group to 10 inches.

95 grains was a little on the hot side with the 208's

 

[Overkill338]

Would you guys consider it acceptable as long as you got over 3000 with a 200gr bullet and got good accuracy ? Or do you like your rifles to run at top speed ?

 

[Varmint Hunter]

I always wondered why anyone would own a 300 RUM and shoot it @ 300 Win or 300 WBY velocities. There's certainly nothing wrong with doing it, it just seems odd to me.

However, I did notice that many posters are quite happy to get good accuracy even if the velocity is 200 ft (or so) less than the maximim listed velocity.

 

[MontanaRifleman]

The reason I got a RUM was for velocity and range. You can back it off but why not just go with another cartridge and save a lot of powder and some recoil? We all have our priorities and goals. I can get 3200 fps with a 180 bullet out of a 300 WSM and 3400 out of the RUM with a lot more powder and recoil. I have considered quite a bit if it's worth it. So far, I think it is.

 

[Iron Worker]

The reason I got a RUM was for velocity and range. You can back it off but why not just go with another cartridge and save a lot of powder and some recoil? We all have our priorities and goals. I can get 3200 fps with a 180 bullet out of a 300 WSM and 3400 out of the RUM with a lot more powder and recoil. I have considered quite a bit if it's worth it. So far, I think it is.

How are you getting 3200 with a 180 gr bullet out of a 300 WSM ?

 

[300spanker]

Tang,
I shoot the exact load you want, shot a mule deer in 2008 year at 485 yards. 200 grain sierra game king 95.5 grains of retumbo oal is max in ur magazine. however the 200 game king is an elk bullet as far as im concerned it has a thicker jacket and more antimony in the lead. shot 1/2 inch groups all day. last year i went to the JLk vld 210grn. long boat tail, higher bc, at 94.0 grains of retumbo. oal 3.745 its a deer slayer. high bc. if u love sierra try the new 210 vld sierra matchking or 220 grain match, but don't shoot deer with 240 matchking they won't expand on deer at long range. I like that 210 JLK LBT, they use a J-4 jacket like berger.gun)

 

[MontanaRifleman]

How are you getting 3200 with a 180 gr bullet out of a 300 WSM ?

With 67.5 of RL17. The actual average velocity was 3193 out of a 24 3/8" barrel - 1" less bore length than the RUM.

 

[Overkill338]

I agree on getting the speed. I have a .300 Win Mag already. Odds are, I might not ever need something bigger than a .308 Win, but it's nice to know I have it if I do need it. I do sometimes wonder if I should have ordered my Sendero in .300 Win Mag.

But, Im trying to obtain 3100-3150 with a 200-210gr bullet, and get 1/2" or less groups. I'm working with Retumbo, Fed 215 GM primers, and Rem brass.