260Rem Reloading Questions

[ctimgo]

I have a new DPMS LR260 and tried some handloads today. I have only shot 20 rounds through the gun till now. I am using Remington brass trimmed to 2.030, CCI primers, Varget powder (38gr to 39.5gr in 3gr increments), coal 2.750. The results not very good. None of the loads were hot enough to cycle the bolt back far enough to load another rounds or lock open when the mag was empty. Best group was 1.5" which was the 39.5 load and they did tighten up the closer I got to 39.5. Velocities all over the place. I'm already over the max load from the Hodgdon's web site. Their loads are using a bolt gun so should I use more because of shooting a gas gun and I lose some gas to work the bolt? Any info would be greatly appreciated.

 

[climbnjump]

Which bullet?

ETA:
You might want to try a slower burning powder to move the pressure peak closer to your gas port.

 

[ctimgo]

Bullet

The bullet I am using is the Hornady 123gr A-max.

 

[rcmodel]

I don't even see Varget listed with a 123 grain bullet on Hodgdon's web site???
So what data are you using??

Does the gun work with factory loads??

rc

 

[Sunray]

A 123 is probably just too light for the .260 Rem out of your rifle.

 

[climbnjump]

I don't even see Varget listed with a 123 grain bullet on Hodgdon's web site???

No, they recommend using the data for 129 gr bullets for the 123 Amax.* But Varget is the fastest powder they list for that application. Probably one of the 4350's or 4831's might work better.

ETA:
*Or at least they do in the 9th Ed. Handbook - I haven't checked the website.

 

[Sunray]

There's 125 grain Varget data, but I don't think it'll help. Reviews of your rifle are all showing 140ish grain bullets.

 

[ctimgo]

Load Data

I know they don't have load data for the 123gr and Varget but they do for the 120gr and the 125gr so I tried to get in the middle of those. A lot of people have good success with Varget and I have 8lbs on hand. I the first 20 rounds that were shot out of the gun were factory Remington and worked perfect. I did notice that the brass also ejected much further with the factory ammo. So with not having any signs of pressure should I keep working up the ladder and see if things get better?

 

[rcmodel]

Your call I guess.

But if the burn rate of Varget is too fast or too slow for the gas port.

You could blow it up before you get it too work right.

Chamber pressure and gas port pressure are two entirely different things.

rc

 

[climbnjump]

A lot of people have good success with Varget and I have 8lbs on hand.

Yes, Varget is good stuff and many shooters swear by it. But in your specific caliber/bullet/rifle combination?

I'm already over the max load from the Hodgdon's web site.

So with not having any signs of pressure should I keep working up the ladder and see if things get better?

Sure. Like RC said, you can keep going until you either get consistent ejection or a blown up receiver - whichever comes first.

Or, you can bite the bullet (sorry) and choose a bullet/powder combination that will work well for your rifle w/o excessive pressure.

 

[243winxb]

Load 3 rounds at 36 grs. And see what happens. A load thats to hot will have hard extraction from the chamber, slowing the bolt velocity. Look for damage to rim of the brass. Worth a try? Thats my guess. But more likely a port pressure problem? ? as already said.

 

[GooseGestapo]

Change powders.
IMR4350 is the fastest powder I use in .260.
The 123 gr Hornady is my favorite bullet. I seat it to touch rifling (not jammed, just lightly touching), over47.0gr of RL22. This is top load for my rifle so loaded. Max is 49.0, but seated to2.780", not 2.835".
Shoots at/under moa from my Rem. Mod-7. 2,850 fps 20"bbl.

 

[ctimgo]

No signs of pressure problems

If the loads were getting to hot for my gun wouldn't I be getting some sort of sign that there is to much pressure as I worked up? The brass looks the same for 38gr as it does for 39.5gr.

 

[243winxb]

Reduced load just something to try.

Pressure signs are not alway easy to see in autos. It may take over 65,000 PSI.

Cartridge Brass-
Material is 70 copper/30 zinc with trace amounts of lead & iron , called C26000. Material starts to yield at 15,000 PSI when soft (annealed), and 63,000 PSI when hard.
Material yields, but continues to get stronger up to 47,000 PSI when soft, and 76,000 PSI
when work hardened..

I was looking at this Hornady data. Its not the same bullet. Shows 37.1 gr maximum. https://www.ar15.com/archive/topic.html?b=6&f=42&t=372623 Yes, Different components = Different pressure. Not the bullet your using. SAAMI shows a working pressure of 60,000 PSI for the 260 Remington.

 

[climbnjump]

If the loads were getting to hot for my gun wouldn't I be getting some sort of sign that there is to much pressure as I worked up?

As noted in the post above, max SAAMI working pressure for the .260 Rem is 60,000 psi.

Inputting your 39.5 gr Varget with the 123 gr AMAX and 2.75 COL into QuickLoad gives a max pressure of 57,440 PSI.

What this actually means is that due to variations in components, you may already be OVER 60,000 psi.

For instance, one small change to the inputs I used - reducing QuickLoad's default case capacity for the .260 by one grain of water - will boost the pressure to 60,000 psi.

So, you are already at max pressure, you're getting inconsistent velocities, unacceptable accuracy and poor bolt cycling.

Loading up over max pressure isn't going to solve your existing problems and may well give you new ones that will be even more unacceptable.

 

[Cypress]

Give RL 19 a try. Gave the best accuracy and velocity in my .260. All tested groups were acceptable. Don't recall the charge right off hand but it puts 120 grain Hot-Cors and Pro Hunters in the same 1" bull.

 

[ctimgo]

RL19 Temp sensitivity

I think RL19 would be to temp. sensitive for me. Thanks

 

[BigBore45]

Your over your guns pressure limit. Go back down to the start load and soak the bolt and carrier with oil, the dpms needs a lot of oil to break in trust me.

 

[ctimgo]

Hodgdon 4350

I want to try h4350 but can't find any but I can find IMR4350 so I may give it a try. Most people are using 4350 and getting better velocities with it. Anybody?

 

[otrman]

Before you give up on Varget and seeing you have 8 lbs. of it, try some heavier bullets. In my experience with Varget and semi autos, heavier bullets seem to work better than lighter ones.

 

[capreppy]

On other boards, people have had success with the 260 Rem and 6.5 Creedmoor with the 120gr class bullets and Varget. However, I'm not sure I've seen anyone running a gas gun. Those that have had success have run this combo on bolt guns.

I run H4350 which is the defacto powder for the two cartridges. There are other options, but you will give up speed or pressure or both or more.

You may want to try one of the 100gr class of bullets. I've seen some have some success with that class of bullets and Varget in a gas gun.

 

[ctimgo]

Internal Ballistics

Are there any free internal ballistics programs online or for download? I would like to have Quickload but can't afford it. I did a search but couldn't find anything.

 

[farmerboy78]

I have a Creedmoor (very similar) and I use the 123gr hornady amax and 42gr of accurate 4350

 

[ctimgo]

Is youre creedmoor a gas gun?

Farmerboy78 Is your creedmoor a gas gun? Any problems with bolt not cycling far enough to pick up next round?

 

[USMC-Johnson]

I have a friend with a custom 6.5cm gas gun (AR platform). His will just barely cycle the 120gr factory Amax stuff but has no problems with the 140 factory stuff or the 120gr superformance factory ammo.

My advice is to step up to the 140 amax if your rifle will stabilize it. If not at least try getting up to the 130gr stuff and a faster powder.

My bolt gun shoots varget like crap in 6.5cm where as my 308 loves it.