22-243 Retumbo loads

[cinch]

Is anyone using Retumbo in their 22-243 Winchester? I am shooting the 75gr Amax with 48grns of Reloader25 currently. My barrel is an 8 twist. I would like to switch to Retumbo since I am using it in about 4 other guns right now. I was curious if anyone is using it and what would be a good starting load. Thanks in advance, cinch

 

[Okiecat]

Cinch, I was shooting Retumbo in mine. It seems to lack a little vel. I was about a grain over max and was loosing a few rds of brass every time. But it also produced my best group ever. I would say to start at 45 with 47.5 max. I was shooting 80 gr. bullets jammed .010 to .015. By the way I have tried 7828 just recently and looking for a starting load with Magnum!!!

 

[Iron Worker]

Okiecat more details please

What is muzzle velocity of your 22/243 shooting 80 gr bullets? Who makes your BBL? Rate of rifling? Barrel length? Barrel life? I'm shooting a 22-250AI with a Mike Rock 5R Cut rifled 8" twist BBL . I don't have quite 500 rnds through it and throat erosion is evident .

 

[mikebob]

I shoot 47gr retumbo 90gr bergers .007 in and lapua brass and not at max. My throat is long though, i couldn't get enough pressure out of retumbo with 80 gr bergers or amax's, velocity was about 150fps slower and getting powder down bbl. I have loaded my lapua brass about 7 times each and still good. You have to make sure you dont bump shoulder back to much or you will loose alot of brass with this round. 47gr with 90gr is a compressed load and 48gr with 80gr amaxes is compressed enough it was putting dent ring on the bullet but still wasnt at max for me. I think if your going to shoot retumbo youll need to shoot 90 grainers which you should be able to do mine is a 1-8 twist. I was going to try 4831 with the 80's but i tried the 90's and they worked so i went that way instead. If i remember right i was getting 3450 with 46gr r22 and 80gr bergers which was a max load in mine with a long throat. With mine i seamed to have best accuracy around 3400 with 80gr.

 

[Iron Worker]

I don't see the advantage

In my 22-250AI with "8" twist the Sierra book says I can get 3,300 with 80 gr bullet. I was loading 39grs of H4350 and getting 3,450 with 75gr A-max. Now you say out of a 8" twist BBL you can shoot a 90 gr bullet? I thought that bullet requires a 7" twist? Were those 90 gr Berger bullets?

 

[Varmint Hunter]

For whatever it's worth - I tried H870 in my 22-243AI with 75gr A-Max bullets. A FULL case of H870 was EXTREMELY accurate but produced low velocity. I'd suspect that Retumbo would also be too slow for top velocities with a 75gr bullet. Why shoot a 22-243 if you're not into velocity?

 

[cinch]

Thanks for all the replies. This will give me a good place to start. I am using Retumbo in 4 other rifles right now. It is alot easier to stock up with a bunch of powder if you can keep them the same. Thanks again, cinch

 

[mikebob]

In my 22-250AI with "8" twist the Sierra book says I can get 3,300 with 80 gr bullet. I was loading 39grs of H4350 and getting 3,450 with 75gr A-max. Now you say out of a 8" twist BBL you can shoot a 90 gr bullet? I thought that bullet requires a 7" twist? Were those 90 gr Berger bullets?

it will shoot them faster but best accuracy was around 3400-50

my bbl is hart 1-8 twist and it does shoot 90gr bergers. I shot some 90gr sierra to and they shot fine. I think it will shot the 90gr in a 1-8 because of the velocity of the 22-243. I have shot mine at targets to 1200 yards without any problems from the 90 gr bergers.