7mm RM - 160AB Loads

[TXbaldhunter]

I haven't loaded any 160's with Reloader-22 yet,but I did load some with IMR-4350.I worked up to 65.3grs of IMR-4350,but it's really a little hot for the 160's,but it does OK with 140-150gr bullets.I was getting 3150fps with 160's and it grouped under an inch,but I think around 3000-3050fps would be what I'd be happy with these days.I think around 63.5grs would put me right there.I've been loading 69.5grs of Reloader-22 in my 7mag with 140gr bullets.I'm not at max yet and I'm getting 3200fps and near one hole groups.I may work up a load using Reloader-22 for it with 160gr Accubonds.I think around 67.0-68.0grs will put me right where I want to be.Just remember,all rifles are different so as always,start low and slowly work your way up.

 

[Richracer1]

Update, the RB trigger is installed and set around 2 3/4 to 3lbs. Whole hell of a lot better that the original, no more creep and don't need a come-along. We'll be going out to have him check the sight-in as he shoot's lefty. Plus I have a few more RL-22 charge weights to try as I never found the max yet. Keep your fingers crossed.

 

[Richracer1]

Update #2:
Went out so the young man could sight it in, get use to the new trigger, and I shot 4 more RL-22 charges at 3.400" COL:
(Velocities from the 66 and 67.5 charges ranged from 2900 to 2985.
66gn was crap
66.5gn achieved a .895" 3 shot group at 2950fps (64.5 shot a .926" group at 2840fps)
67gn was crap
67.5gn achieved a 1.201" group.

He's going to use the 64.5gn round for deer season as I don't have time to unload 51 rounds of 64.5gn and load them up again with 66.5gn and have him verify his scope adjustments. I'll work the unload/load after hunting season if he wants me too. The ballistic charts show only minor tragectory differences between the two but the energy is a decent change (2865 compared to 3092 @ muzzle):
64.5gn (2840) 2.7" high @ 100yds is 3.6" low at 300; MPBR is 289yds w/a 245yd zero - theoretically
66.5gn (2950) 2.5" high @ 100yds is 3.3" low at 300; MPBR is 300yds w/a 254yd zero - theoretically

 

[SJB358]

Looks good Rich. Nothing shabby about a 160gr AccuBond at 280+ speeds! Should be a great deer/elk getter for sure. I am sure he is happy. Hope the new trigger is working out well for both you during load development and hunting for the lad. Seems like data for RL22 is really on the soft side. I had to push into the 66gr range in order to get near 3000FPS. I am thinking of trying something a little slower and seeing what the results would be. Scotty

 

[Richracer1]

RL-25 or Retumbo should work. I didn't have any RL-25 and having 3 RUMs that use lots of Retumbo, I didn't want to use it on his rifle.

 

[SJB358]

I will give it a try in one of my 7RM's soon I think. Seems like H1000 is a good one also. I am sure one of the guys on here could run a QL and see where they fall out. I do think a slower powder would probably have a better chance of reaching speeds advertised in the manuals. Not that I have had any pressure signs with RL22 going up to 3gr's over max though. Scotty

 

[Richracer1]

I didn't have any pressure sign at 67.5gn today, but it was also in the low 40s.

 

[JD338]

Rich,

Sounds like work in progress. Glad you got the new trigger, should make a big difference.

Any luck with shimming the action to float the barrel?

JD338

 

[Richracer1]

Rich,

Sounds like work in progress. Glad you got the new trigger, should make a big difference.

Any luck with shimming the action to float the barrel?

JD338

Probably try that next spring - don't have the time to mess with his rifle now - too much going on getting the RV winterized, preparing for my elk hunts and I'm also building a trailer for my sled.