Looks like it will shoot, custom M7 load development

[Chuck R.]

So after 60+ rounds of screwing around during practice and barrel break in I'm finally doing some load development for my little .260Rem for this hunting season. The details on the rifle are here:

https://www.thehighroad.org/index.php?threads/rem-m7-custom-done-finally.902492/#post-12228636

As I said in the initial thread, this was my idea of "the prefect eastern KS whitetail rifle for blinds and stands". Goal was for a 7LB "all up" 300 yd capable rifle. I busted the weight by 8 ounces. During barrel break in it did very well with cheap PPU 120, so I loaded a bunch and have been practicing with it out to 460yds. I don't normally get serious about load development until I've got 50-75 rds down the tube anyway and I hit that yesterday morning. Break-in group with 120PPU:



So I started this morning with H4350 and Nosler BTs all groups were 4 rds, because I normally do 5 initial loads for testing using the OCW method and 5x4 equals a nice even 20 rds. Everything I tested held at under 1MOA, except for a flyer on Group 2. The 2.5-8x36 scope isn't exactly benchrest material, but that's not what I put the rifle together for. There was a little 5-6MPH varying 3:00 wind.

1st group, a little too slow for my purpose, 2870:



3rd and 4th Tests:



the gun (again):



Going to go with the 4th load which clocked at 2940, it duplicated my MV with the OEM barrel with slightly less powder. 5th load group was just around .85MOA and at 2963 FPS. The new 3 groove barrel appears to be about 25-30 FPS faster than the OEM barrel, whether that's the 3 grooves or the normal "it's just faster" is beyond me. Running the numbers it gives me an MPBR of about 290 yds on a 6" kill zone, so I lose about 20yds from my 8.5lb 24" barreled .270.

For about 85% of my hunting 75-200yds the little M7 will work.

 

[LoonWulf]

thats a sexy rig! shoots ok too lol!

 

[rayatphonix]

I like the rifle! What grain BT’s are you using? Judging from the velocity I’m guessing120’s?

 

[Chuck R.]

I like the rifle! What grain BT’s are you using? Judging from the velocity I’m guessing120’s?

Yup, 120s.

I tried 3 test rds with 130ABs yesterday also, just trying to sort out pressure and MV. The 3 rds ( different loads with a .9 grain spread ) went sub MOA, but the highest MV was at 2750. I was hoping to get 2800 and use that for my all around load. No signs of pressure, so I'll up the charges some.

Like any light rifle it's a challenge to shoot well off the bench. Some of the groups I've gotten seem to be due to failing concentration on my part as I eased/changed my grip.

 

[rayatphonix]

I developed a good load with Barnes TTSX 120’s this summer. That’ll be my hunting load for the Creedmoor I’ll hunt with this year. Velocity is somewhat disappointing, but the consistency is very good.

 

[Chuck R.]

I developed a good load with Barnes TTSX 120’s this summer. That’ll be my hunting load for the Creedmoor I’ll hunt with this year. Velocity is somewhat disappointing, but the consistency is very good.

What powder? I'm using H4350 over FED210s.

I've got to try some Barnes, but the $$$ keeps me away. My cheap PPU 120HPBT practice load is very cost effective and although it starts out slower pretty much mimics the 120BT trajectory. I've also managed to scrounge about 10years for of 120BTs at "some practice and a couple deer a year" usage rate.

 

[rayatphonix]

RL 17 has worked very well for me over the years. I’ve got one load that does well with H4350, but not with this particular rifle. Velocity is right at 2800 fps.

 

[horsemen61]

.260 Remington man I want one one day I’ll have one!
@Chuck R. thats a good looking handy rifle!

 

[rayatphonix]

Here’s one of the rifles I’ll hunt with this year. Bergara Stalker with a Steiner scope.

 

[Chuck R.]

RL 17 has worked very well for me over the years. I’ve got one load that does well with H4350, but not with this particular rifle. Velocity is right at 2800 fps.

Right now I'm sitting on 5lbs of H4350 and really the .260 is my only outlet for it.. Worse comes to worse I'll just stick with the 120s and the H4350 loads. I worked up 5 more pressure/velocity test rounds for the 130ABs and I'll probably try them out tomorrow when I get home from work. I've also read that RL17 gives great velocities in .260, so maybe I'll get my hands on some. Luckily there's a boat load of old load data available on forums from when the match guys picked up on it before the 6.5C came on the scene.

.260 Remington man I want one one day I’ll have one!
@Chuck R. thats a good looking handy rifle!

It's a re-barreled....wait for it....260Rem! Was thinking of doing the 6.5C or .260AI, but had dies, brass etc. so just stuck with the .260rem. My son and I shot it stock for 7 whitetails and I really liked how well it did out to 200. For my intended ranges, I wouldn't benefit a whole lot from the .260AI and I just add a fireforming step. Brass is everywhere and just a sizing die away from being .260. I'd hoped the 3groove barrel would add a few FPS based on what I'd read, but I just don't know. I do know that it cleans like a dream, so maybe that benefit is true.

With the lighter bullets it does a little better than the 6.5C and since I'm using it only on deer I don't need the 140s. It really is a cool little gun. The 20" 2B profile balances well in the Manners stock and the little 2.5-8x36 compliments the overall scale of the thing. I was shooting it off-hand on SAT and it "hangs" well, just enough weight up front.

 

[Chuck R.]

Here’s one of the rifles I’ll hunt with this year. Bergara Stalker with a Steiner scope.

Very good looking rifle!

 

[GooseGestapo]

I too have a REM Mod-7 in .260.
It’s also a tack driver.
With 43.0gr of RL17 it gets 2870fps with a PPU 120gr BTHPT Match. Shoots about 0.6”five shots at 100yds.
However, it’s got a 1-10.9” twist barrel by actually measuring the twist rate (factory claimed 1/10” at the time this gun was made.)
It shoots “patterns” with a 129gr Hornady SST, and won’t hit the 100yd berm with a 140gr SST.
BUT, it shoots a discontinued 160gr Sierra RNSpt to about 1-1.2 MOA over 43.0gr RL22. @2,500fps.

My favorite deer load is the discontinued 120gr Speer HotCor. Over 47.0gr of RL22, it gets 2850fps, below 1moa and is a perfect deer slayer. Secondly, the Speer 140gr HotCor over 45.0gr to 2,650 and also drops deer with authority.

Shot this one last year with the .260. LOONG shot at 17yds!,, 120gr Speer HotCore.

 

[Chuck R.]

Guys,

I've not played with RL17...temp sensitive or OK? The reason I switched to H4350 and H4831Sc years ago was to gain some temp stability. We go through these KS temperature swings right around rifle season..

 

[NMachine]

I had a .260 for a while. I really enjoyed it, but a friend really wanted it an I sold it to him. I had excellent results with RL16. I was living in NM at the time and RL16 proved itself extremely temp stable in temps from 100+ to low single digits. I got better velocity with it than most other powders I tried including H4350. It worked great with 120gr to 140gr+ bullets. Accuracy was outstanding.