6.5 CM or 260 Rem

If you went all the way to "blowing primers to find max", you really need to learn how to find signs of pressure. No way did it go from a safe load to blowing primers in any reasonable charge weight testing jump. No cratered primers, flattened primers, case head swipe, sticky bolt lift, pronounced click on primary extraction, ejector marks, etc.? You never mentioned your charge weights.

I had a .260Rem w. 14s & H4350 in a 26" Bartlein. Only could manage 2920fps in a safe but hot load.

I had a 28" 6.5SLR w. 140 & H4350. 2960 fps was absolute max, on the verge of pressure for a hunting load.

I would hate to see you in the Darwin Awards contestant list.
I've never had a bolt stick. It's not like I loaded it so hot the primer was falling in my hand. I could see it was just not flat in the primer pocket.
 
I've never had a bolt stick. It's not like I loaded it so hot the primer was falling in my hand. I could see it was just not flat in the primer pocket.
if you had primers slightly ejected, they should've been shoved back in and flattened when you fired them. You should've had ejector marks before that happened. How many firings are you getting out of your brass with your current load?
 
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If you went all the way to "blowing primers to find max", you really need to learn how to find signs of pressure. No way did it go from a safe load to blowing primers in any reasonable charge weight testing jump. No cratered primers, flattened primers, case head swipe, sticky bolt lift, pronounced click on primary extraction, ejector marks, etc.? You never mentioned your charge weights.

I had a .260Rem w. 14s & H4350 in a 26" Bartlein. Only could manage 2920fps in a safe but hot load.

I had a 28" 6.5SLR w. 140 & H4350. 2960 fps was absolute max, on the verge of pressure for a hunting load.

I would hate to see you in the Darwin Awards contestant list.
When I had my barrel installed the gun smith asked me to bring 5 rounds Of loaded Ammo at the length I wanted them to be. That way he can customize everything. I'm not a gun smith so I probably can't explain all the details. I know my 260 bullets will not fit in another 260. I won't be on any Darwin Awards anytime soon. I've been reload for almost 40 years. I thank I'm good. I dont like posting my grains of powder I used in my guns. There mite be someone else on Darwin Awards.
 
When I had my barrel installed the gun smith asked me to bring 5 rounds Of loaded Ammo at the length I wanted them to be. That way he can customize everything. I'm not a gun smith so I probably can't explain all the details. I know my 260 bullets will not fit in another 260. I won't be on any Darwin Awards anytime soon. I've been reload for almost 40 years. I thank I'm good.
It's doesn't make sense, your primers would appear flattened if they were slightly ejected from firing. They don't protrude after firing. The case head slams into the bolt face when fired, so and primer that was protruding would be flattened. This usually happens with new oversized brass or brass you oversized.
You claim 250 FPS over the creed, with a 27" custom barrel to a sloppy bore factory Remington.
 
It's doesn't make sense, your primers would appear flattened if they were slightly ejected from firing. They don't protrude after firing. The case head slams into the bolt face when fired, so and primer that was protruding would be flattened. This usually happens with new oversized brass or brass you oversized.
You claim 250 FPS over the creed, with a 27" custom barrel to a sloppy bore factory Remington.
Sloppy Remington action. LoL!!! Guess that's why all the aftermarket companies base all their actions off the Original Remington action. LoL!!! I needed that. Thank you sir.
 
...Now I DON'T recommend this unless you are an experienced reloaded and know how to look for pressure signs. I did load my 260 hot enough to blow primers to help me find my max charge on ( MY ) rifle with my chosen powder. I then wrote down the grains of powder that blew my primers out. After that I performed a latter test to find the charge my 260 liked. It is way below the charge that was blowing primers. I use this method on all my rifles.

Wow... you just can't make this stuff up...

You do realize that if you're seeing pressure signs, ie flat primers, ejector marks, etc, that your generally in the 70,000 PSI+ range right? Blown primers to find pressure?! You've got to be kidding me...

Also, everything else being equal, velocity increase with case capacity is only about 1/4 the percentage of increase in volume. A .260 holds about 2% more powder than the Creedmoor so is only good for about 14fps more than the Creedmoor when loaded to equal pressures.

You may be getting 250 FPS more out of your .260, but if you are, it's because you are running significantly higher pressure than you are in your Creedmoor.

John
 
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They probably wouldn't appreciate any modifications to their rifle and probably say no. I do have an extra .308 with a 24" barrel that I could swap. Probably come out cheaper.
Call them and they'll swap it. Give them the new barrel you want on it.
At lest call them and ask. I know a guy who had them re-barrel his rifle.
 
Wow... you just can't make this stuff up...

You do realize that if you're seeing pressure signs, ie flat primers, ejector marks, etc, that your generally in the 70,000 PSI+ range right? Blown primers to find pressure?! You've got to be kidding me...

Also, everything else being equal, velocity increase with case capacity is only about 1/4 the percentage of increase in volume. A .260 holds about 2% more powder than the Creedmoor so is only good for about 14fps more than the Creedmoor when loaded to equal pressures.

You may be getting 250 FPS more out of your .260, but if you are, it's because you are running significantly higher pressure than you are in your Creedmoor.

John
I don't know the psi I'm in. I don't have a way to measure it. My primer pockets were fine. My cases were not split. Bolt don't stick. Barrel still extremely accurate. I don't know about 2% difference I just know the water coulomb on my 6.5 Creedmoor is 52.4 and my 260 Rem is 54.3. Max pressure for the 260 is 60,191 psi and the Creedmoor is 63,091. I guess that has something to do with the shoulder of the bullet. Not sure. Now my 260 holds 1.5 more grains of powder than the 6.5 Creedmoor and that's quit a bit to me. But again. The pressure numbers above are from the factory. I don't have a way to measure them myself. The water columns above I measured myself after brass has been fired. So I don't know what to tell ya. Maybe I got a fluke action on my Creedmoor. It shoots great. No complaints. Try this, take 1.5 grains of powder out of you 6.5 Creedmoor. I would all most bet it would slow down more than only 14fps. So I'm not gonna change anything on my Creedmoor. As far as I'm concerned it's done.
 
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I've never had a bolt stick. It's not like I loaded it so hot the primer was falling in my hand. I could see it was just not flat in the primer pocket.
Then you do not know the difference between a "blown primer" and "flattened primer". And probably a "cratered primer" or "pierced primer" either. 40 years of hand loading does not necessarily equate to good loading practices.

I could very well be mistaken. But with the info you have given, I am suspect.
 
I've had a few people ask me this question and here's the answer I give them:

If you are going to reload your own ammo, think hard about the .260 as they can run a little faster if you want them to. That velocity will pay dividends out past 700 yards. I've heard some people say and post that the 6.5 is an "inherently more accurate round" than the .260 due to its case design, but I've never been convinced. The 6.5 is still a great round and if you and your friend don't have time to load ammo, decent factory ammo is plentiful and will be for a while since SOCOM adopted the 6.5. Last year I put together a .260 Remage and it shoots great but if I'd known SOCOM was going with the 6.5 I would've given more thought into getting the 6.5. I load most of my own stuff though, so I think I still would've gone with the .260. That being said I might shoot a bit more if I could just run to walmart and pick up match grade ammo. So far I've only run 140 and 143 grain projectiles and I'm happy with the results.

I don't know if you plan on building your own gun or buying off the shelf, but Proof Research is building spec barrels for the Bighorn Origin action. I've not seen it done yet but they claim you can just screw the barrel on, torque it and you're ready to go. 6.5 is one of the few calibers they offer for the origin (not the 260), I'd be tempted to try that today if I needed another 6.5/264 caliber rifle. My Remage barrel is a McGowen and I'm happy with it.

As far as hunting goes, I don't know that I'd use either round on an elk past 500 yards (full disclosure, I've never tried to kill an elk but I'm planning to), but just me personally I don't think I'd take a shot with anything much past that distance. For deer and pigs, I think 6.5s/.264s are perfect. That's just me though, shot placement is key.

Good luck and enjoy the new shooter.

-Brad
 
I don't know the psi I'm in. I don't have a way to measure it. My primer pockets were fine. My cases were not split. Bolt don't stick. Barrel still extremely accurate. I don't know about 2% difference I just know the water coulomb on my 6.5 Creedmoor is 52.4 and my 260 Rem is 54.3. Max pressure for the 260 is 60,191 psi and the Creedmoor is 63,091. I guess that has something to do with the shoulder of the bullet. Not sure. Now my 260 holds 1.5 more grains of powder than the 6.5 Creedmoor and that's quit a bit to me. But again. The pressure numbers above are from the factory. I don't have a way to measure them myself. The water columns above I measured myself after brass has been fired. So I don't know what to tell ya. Maybe I got a fluke action on my Creedmoor. It shoots great. No complaints. Try this, take 1.5 grains of powder out of you 6.5 Creedmoor. I would all most bet it would slow down more than only 14fps. So I'm not gonna change anything on my Creedmoor. As far as I'm concerned it's done.


I sincerely hope you are never testing handloads while we're sharing a range. You may have been reloading for 40 years but you clearly haven't been doing it safely.


Let's start with what you 'know', the maximum pressure limits for the .260 Rem and 6.5 CM. You say 60,191psi for the .260 and 63,091psi for the 6.5. Wrong. SAAMI specifies 60,000psi for the .260 Rem and 62,000 for the 6.5 CM.


If you are blowing primers there are multiple possibilities including the most likely, headspace issues or excessive pressures. Since you've been doing this for years, I suspect the latter.

But I agree with others, it sounds like you don't know what a blown primer is.
 
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