Gunsmithing Ruger RPR 6.5 CM

[Joey Fletcher]

Hello Everyone

Does anyone know the best way to find the ogive on one of these rifles... I have tried 3 of the 4 ways I know should work but I can not get within a mile of the same numbers. This gun shoots so good with Federal Premium Gold Medal Match, I am trying to copy this load but everything I load shoots like Buck Shot. I got mad 2 days ago and made up a dummy round. 2.980, dropped in in and closed the bolt...It was tight but closed with out a lot of pressure. Open the bold and the round had 7/16 inch marks where it chambered and locked. Measured the dummy round at 2.978 after it was fully closed and locked.
Is this a 5R issue or what?
I do not want to take this barrel off to slug it. I am not sure I could get it back to the way it shoots with factory ammo. I have always heard if it ain't broke don't fix it.

I am an Ol'Man on SS so it is hard for me to shoot this factory ammo as much as I want to shoot this thing at 1000 yards. I have never had an issue with a 7.62 x 51 of a 222 Rem.

Any advise would be taken. This is my first post

Thanks again
Joey Fletcher

 

[bschneiderheinze]

That sounds about right that’s about where the chamber measures on my 6 Creedmoor I tried a hornady chamber gauge and the bullet just fell out. I think some of them just have long chambers. I have another barrel waiting for mine but it shoots lights out so until show signs of giving out I’m not changing it

 

[Easy_E]

If the factory ammo shoots and you have the same bullet to reload cant you copy the seating depth ? You would think if you can get the same seating and same speed as the factory ammo you would be good ?

 

[ZiaHunter]

Joey:

Based on your comments I assume you are trying to determine the amount of freebore in the chamber. Most SAAMI chambered rifles have fairly long freebores to allow for different bullet types and avoid jamming. I tried a number of tools and methods over the years and found the only one that gives me consistent readings is the Hornady tool when used with fire formed brass for that chamber. If the rifles shoots well with factory ammo try to duplicate the load. Have been shooting the 6.5 CM for over 5 years and H4350 has been my goto powder. Experiment with different charge weights to find the node and you should be GTG. An OCW test will help you find it. Take care and good luck.

 

[Joey Fletcher]

OK......this was a new rifle. 7 weeks ago. I got the rifle before I had any ammo for it. Went on GB's and bided on 200 round case of 140 gr FPGMM ammo. I won 2 cases with 200 rds. each, those rounds had 140gr BTHP Sierra. At the same time I ordered 2 boxes each of
140 gr Sierra BTHP
142 gr " "
130gr " TMK
Then I read that the A Max. was the best bullet for the 6.5CM went to order some of but found out they had better bullets called ELD Hornady so I got some of those in 140 gr and 147's

I copied the FPGMM...140 gr. with the sierra 140 in the once fired brass from my 6.5....... I could not get the speed from any of the 3 types of powder I have on hand
H-4350
IMR 4350
Hyb. V 100

Without having high pressure signs.
I am wanting to find the ogive with out tearing down and slugging the chamber

I am having one hell of a time typing on this site...it has taken me over an hour to type this

I will not be posting much on here....to dang hard to type.............Just an Ol'Dumb MAN

 

[Joey Fletcher]

I am going to drill out, and tap one of my once fired cases and use the hornady case gauge and see if I can get some numbers close. The hornady tool is to short to work good in my RPR, my fat fingers have a hard tome trying to lock down the stop screw. Going to replace that short knob with a longer screw

 

[huntsman22]

The old cleaning rod method will get you close.

 

[665.0coupe]

I used the Hornady tool with both the factory barrel and an LRI barrel. The factory locking screw was harder to use but not impossible.

 

[fdkay]

OK......this was a new rifle. 7 weeks ago. I got the rifle before I had any ammo for it. Went on GB's and bided on 200 round case of 140 gr FPGMM ammo. I won 2 cases with 200 rds. each, those rounds had 140gr BTHP Sierra. At the same time I ordered 2 boxes each of
140 gr Sierra BTHP
142 gr " "
130gr " TMK
Then I read that the A Max. was the best bullet for the 6.5CM went to order some of but found out they had better bullets called ELD Hornady so I got some of those in 140 gr and 147's

I copied the FPGMM...140 gr. with the sierra 140 in the once fired brass from my 6.5....... I could not get the speed from any of the 3 types of powder I have on hand
H-4350
IMR 4350
Hyb. V 100

Without having high pressure signs.
I am wanting to find the ogive with out tearing down and slugging the chamber

I am having one hell of a time typing on this site...it has taken me over an hour to type this

I will not be posting much on here....to dang hard to type.............Just an Ol'Dumb MAN

My Dad had a custom 6.5x55 Swede that definitely preferred the 140 SMK over the 142.
The 4350's are really the go to powders for the 6.5 CM.
I haven't heard about much success with the Hybrid V 100.
You might be able to get better velocities with RL17

 

[Joey Fletcher]

Thanks Guys
I was just using the powder I have on hand.
Oh...I just won a case of Fusion 6.5 soft point..... Can I pull the bullets and just replace the 140 soft point with any of the other 140gr BTHP and be safe . The Fusion is rated 2750 fps. while the Fed. Prem. Gold Met. Match is 2675 fps.
I bought some Monster 140gr. BTHP from Midsouth shooter supply I thought I would just try them.
Not sure if this question is in the correct forum..........if not move it or just delete it

 

[LG65CM]

I was in a nice thread earlier with a fellow RPR owner. Who came up with a COAL in the low 2.9s. He was using a Berger Hybrid 140. The longest COAL I've measured was around 2.86-8 ish, using a Nosler 140 RDF. Both are long sleek bullets. Another thing we had in common was our CBTOs which were around the 2.225 " area, plus/minus, depending on the bullet.

My rifle groups good at 100 yds with MVs in the upper 2600s to low 2700s. It also favors 'anything' in the 140 bullet weight area. If H4350 is the go to powder for the 6.5CM, then I'd say 140 is the go to bullet weight for the 6.5CM. Sounds like you have a variety of ammunition to test out. I'd stop buying more for now and I'd shoot what you have until you found the one your rifle 'likes' the best. Then as a couple other members here suggested, try to load the mirror of that and go from there.

I was told before I bought my 6.5CM that they are individual rifles and you have to spend some time in finding a load/cartridge/bullet that it 'likes'. It is likely to like more than one. Also, there are certain rounds my rifle just does not shoot (as) well. The lighter bullets, 120s and 130s for examples. Others shoot these bullets as if they were lazers.

I'm an old guy too. Good luck, lg

PS: Bullets I've had the best luck with: Hornady's 140 HPBT and their 140 ELD-M and Sierra's 142 Matchking. Couple alternative powders to consider are Superformance and Alliant's Reloader -17 (RL-17). Once you get down the road a ways.