6.5 Creedmore with a 10 twist barrel

[huntsman22]

*** would build a creed in a 10 twist? run, Forrest, run......

 

[turkeyfever]

I KNOW!!!!!!!!

 

[257Tony]

Are you sure its actually a 10 twist? Most barrel makers don't even offer 6.5's in 10 twist. Most are 8, some are 9 or 7.

 

[turkeyfever]

No I am not sure what it is at this point. He was told that it was a 10 twist from the guy that put the barrel on the action. I am a bystander trying to help him out. I believe that it is a GreenMountain barrel but not sure. At this time it is cheaper for him to keep shooting and trying to find something that works.

 

[SealT5]

123gr amax with varget. Buy him a few hundred and load them up. It will kill any deer in North America. The Gemsbok in my avatar was taken with a 6.5x47L shooting 123gr amaxs. Being a creemoor it could probably take down an elephant

 

[codyadams]

Well I guess out of curiosity you could check the twist, put a tight fitting patch on a cleaning rod that can freely spin, and wrap a piece of tape around the rod that comes together to make a "flag", start the rod in the barrel and with the flag in the strait up position, mark where the rod meets the rear of the reciever, push the rod forward until the flag makes a complete circle, mark the rod at the same point of the reciever again and measure between the two marks. This will be your twist rate. I'm even curious now ha ha.

 

[jebel]

From what I calculate, the only thing you're able to stabilize with a 1:10 twist in this rifle is a short 100 grain with a ballistic tip, like the Barnes TTSX 100 grain as an example. But take even one step up to the 120 grain TTSX and you lose stability.

I'm running those numbers assuming sea level.

 

[SealT5]

I've stabilized 130's in a 1/9 twist bartlein 6.5x47L with a 16.5" barrel. Put varget or 8208xbr behind it and see what they will do. I never could get the 100gr Sierra or 95vmax to shoot under .75moa. Not acceptable in my guns

From what I calculate, the only thing you're able to stabilize with a 1:10 twist in this rifle is a short 100 grain with a ballistic tip, like the Barnes TTSX 100 grain as an example. But take even one step up to the 120 grain TTSX and you lose stability.

I'm running those numbers assuming sea level.

 

[SealT5]

This. I will get you close you the twist rate. But honestly the rate isn't going to affect accuracy that much. 2-3" groups is pretty poor accuracy in my opinion. I'd be looking for other things causing this.

Well I guess out of curiosity you could check the twist, put a tight fitting patch on a cleaning rod that can freely spin, and wrap a piece of tape around the rod that comes together to make a "flag", start the rod in the barrel and with the flag in the strait up position, mark where the rod meets the rear of the reciever, push the rod forward until the flag makes a complete circle, mark the rod at the same point of the reciever again and measure between the two marks. This will be your twist rate. I'm even curious now ha ha.

 

[turkeyfever]

I think that the barrel is junk to start with. Second I think that the chamber is sloppy. Brass is stretching 10 thou in roundness from new brass when first fired. I did check the twist with cleaning rod and it is a 10 twist.

 

[Alibiiv]

Helping a friend out. Have a semi custom 6.5 creedmore with 10 twist barrel. Deer hunting rifle only my friend is in his 70's. Will not be shot over 200 yrds. He has chased a lot of rabbits trying to get this rifle to shoot. I have a factory load shooting Winchester 125 XP shooting around 2 inches on average out of a box. He is very stubborn and old school with his thought process. He wants to shoot 143 eldx but groups are 3 inches or more. I would have bought another barrel by know but he has no funds left, and I not sticking anymore $$ except reloading. Anyone have thought on where to maybe get this rifle shooting under 1 1/2 at 100.

Before I would go nuts with changing loads and looking for another round to make the rifle shoot, I would start with the BASICS! Remove the scope and start from scratch in mounting it. Clean all of the mounting screws off (LocTite), clean out/retap the mounting screws and reinstall the scope bases. I also like to lap my scope rings if you have a scope mounting kit, and torque the entire system down. From what you have written here, you are a shooter and certainly know how to do this. And I'd try mounting a different scope that I knew/know shoots, just in case. Oh and by the way.........................I'm in my seventies, old school, and stubborn (and sometimes cranky), are you making a correlation between the two???????? Remember... we're the lucky ones, we made it this far!! Good luck with trying to figure the dilemma out, sounds like you're a good friend!!! And "ole" guys rule!

 

[jebel]

But honestly the rate isn't going to affect accuracy that much. 2-3" groups is pretty poor accuracy in my opinion. I'd be looking for other things causing this.

I don't think you'll stabilize much over 100 grains with a 1:10 twist from this cartridge, but I agree with this comment, that there seem to be other (additional) things going on.

I would start with the BASICS!

Also agree.

 

[Tex_Hunter]

Based on the twist rate and other details you gave us... load a 120gr ballistic tip over Varget or H4350 and call it good.

I have a pet load using that bullet in a Sporter weight 6.5 Creedmoor that I have for new shooters that I take hunting. At just a shade over 2800fps (my most accurate loads with Varget and H4350 were within 10fps of each other) it absolutely hammers anything downrange of it. I have personally killed a handfull of spikes with it out to 375yds or so, as well as a couple decent sized mature bucks around 75-150yds. Nothing has walked away from this gun yet, most were DRT, one of the bigger bucks that a friend shot this year made it 40yds before piling up.

Unless you are going after something bigger than deer, or trying to extend your range past 500yds the 140gr+ bullets are way too much bullet. The 120s I am running have similar BC and sectional density to a 165gr 30cal ballistic tip, it's plenty for what your intended use is, the only shots that havent been complete pass troughs for me were one I took with a buck quartering towards me, found the cup of that bullet just under the hide on the off side behind the ribs.

 

[jebel]

I'll amend this a bit. First, I still agree that there is likely something else going on besides a slow twist rate (as others explained in better detail above). That said, the 1:10 twist in 6.5 CM is a problem (there's a reason the SAAMI standard is 1:8). Look at the chart below. The far right column indicates stability or not for a given bullet in a 6.5 CM with a 1:10 twist (green good, red bad). On the left you see the bullets I happened to have in my analysis, but the particular bullet matters less than the bullet length (4th column). I've input a few hypothetical bullets at the bottom (yellow), indicating what the maximum length could be in a given bullet weight from 90 grains up to 140 grains and still stabilize with a 1:10 twist. Note: the bullet could be a touch longer than this, if it has a plastic ballistic tip. From what you see here, you need to find short-for-weight bullets; e.g., soft points. However, it is possible. I think the 140 grain Speer Spitzer Soft Point is only 1.20" in length, so works, as an example.

Caveat: as mentioned before, these numbers assume sea-level elevation. They would change a bit, if you live a few thousand feet up (they would improve).

For testing a given bullet for stability, I would recommend the JBM stability calculator, as it includes the adjustment for polymer ballistic tips.
https://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

Good luck.