308 Load Development?

[Michael Eichele]

RL15, and 4064 are two of the best 308 powders but two of the most underrated. Varget is great but it's overrated. I find RL15 to have worked better in more of my 308s and varget has worked better in only a couple.

 

[wjarrell]

Is RL15 as temp stable as varget?

 

[436]

As for temp stable RL-15'..., I "think" M118LR w/ 175gr is loaded with RL-15 because it's so stable, for some reason I beleive I read that a while back, is it "more" stable than Varget? I've shot both hot and cold and I go with RL-15 for my needs.

 

[Shane Lindsey]

As for temp stable RL-15'..., I "think" M118LR w/ 175gr is loaded with RL-15 because it's so stable, for some reason I beleive I read that a while back, is it "more" stable than Varget? I've shot both hot and cold and I go with RL-15 for my needs.

I heard they are no longer loading RE15 anymore due to temp issues. I read somewhere it is now IMR4064. Who knows.

Let the rifle tell you what it likes. My latest 308 has been tough to find a load for, but finally I think I have one worth working a little more. Currently CFE 223 has produced the best accuracy. It isn't stable either...

 

[rustyshackleford]

I heard they are no longer loading RE15 anymore due to temp issues. I read somewhere it is now IMR4064. Who knows.

Let the rifle tell you what it likes. My latest 308 has been tough to find a load for, but finally I think I have one worth working a little more. Currently CFE 223 has produced the best accuracy. It isn't stable either...

I've heard this as well but I've also heard it was reformulated to be more temp stable. I think the temp stability "issue" is overblown in most cases. Seems like powders are pretty well behaved if you shoot them between 85 and probably 20's. I loaded up some rounds with hunter ball powder in 30-06 and we all know ball powder is the devil. So at 68 degrees it gave 2769 ft/sec and at 2 degrees ,according to my freezer, it gave 2711 ft/sec. Both shot over a magneto and both times ES/SD was 8/3 respectively.

 

[Montana'eer]

4064 and 168 AMAX was the most accurate load out of my 308. My best group was .195 five shot group at 100 yards. This was out of a Remington 5R.

I picked up a new .308 5R (and a 6.5CM 5R- screaming end of year deal). Did my barrel break-in / sight in and then started loading. Using 4064 and my second 5 round string produced quite a quite nice group at 120yds.

I think at that point I had 19 rounds down the tube. That was using new Peterson brass, Fed Match primers, 168gr Sierra TMK's..

 

[436]

You may be right the only thing I could find quickly was this.
As you noted, it uses the Sierra 175gr MatchKing bullet. If the cartridges you pulled contain a ball powder, then you have some really early cartridges when they used WC750 powder. For at least the last 15 years, M118LR has used RL15.Jul 16, 2015

 

[rustyshackleford]

I picked up a new .308 5R (and a 6.5CM 5R- screaming end of year deal). Did my barrel break-in / sight in and then started loading. Using 4064 and my second 5 round string produced quite a quite nice group at 120yds.

I think at that point I had 19 rounds down the tube. That was using new Peterson brass, Fed Match primers, 168gr Sierra TMK's..

How much jump?

 

[Montana'eer]

How much jump?

About .10 off just touching. I'm going to move them back to reliably feed and start a little lower and work back up and see what I get.

These are my first new Remingtons and boy this .308 is weird to feel. Using my Hornady gauge I can feel just a bit of tension on the bullet at a certain point- but with just a little 'push'- it'll slide quite a bit until jammed. Same with the 6.5CM. I've recorded two sets of measurements with each rifle- 'just touching' and 'jammed'. I'm staying on 'just touching' for now, lol.

 

[rustyshackleford]

About .10 off just touching. I'm going to move them back to reliably feed and start a little lower and work back up and see what I get.

These are my first new Remingtons and boy this .308 is weird to feel. Using my Hornady gauge I can feel just a bit of tension on the bullet at a certain point- but with just a little 'push'- it'll slide quite a bit until jammed. Same with the 6.5CM. I've recorded two sets of measurements with each rifle- 'just touching' and 'jammed'. I'm staying on 'just touching' for now, lol.

I'll be curious to see how it works out for you. Loaded to 2.850 the 195's were jumping ~.150 and they just never were consistent. Apparently the 30 cal TMK's are all more secant than tangent. I'm probably going to swap to either the 175 Scenar or 185 juggernaut

 

[Montana'eer]

I'll be curious to see how it works out for you. Loaded to 2.850 the 195's were jumping ~.150 and they just never were consistent. Apparently the 30 cal TMK's are all more secant than tangent. I'm probably going to swap to either the 175 Scenar or 185 juggernaut

My velocity with the 4064 is all over the map. That group gave a SD 28 and ES 69. Best was the group before it was 14/39. However I'm not going to get wrapped around the axle with that yet. New gun, new brass... I'll keep recording and see what happens.

 

[Shane Lindsey]

If you have the mag length to load long, I have recently tried the 180 Elite Hunter and it looks pretty promising. Itty bitty groups, but ES is a little high.

 

[rustyshackleford]

My velocity with the 4064 is all over the map. That group gave a SD 28 and ES 69. Best was the group before it was 14/39. However I'm not going to get wrapped around the axle with that yet. New gun, new brass... I'll keep recording and see what happens.

I worked up to the highest node with the 195's using the satterlee method and my ES was probably 10-12 but got fliers no matter the seating. Berger is better about calling it out as to which bullets are more sensitive to depth. The 168 and 185 classic hunter, 175 OTM, along with the 185 Berger juggernaut are all supposedly less sensitive to depth and still have very good BC and form factor relative to weight.

 

[Michael Eichele]

Is RL15 as temp stable as varget?

technically no. That said I've tested it at-10F and +90F. There's not enough difference for me to sweat.Unless you're shooting true double base high energy powder or most ball type powders, temp sensitivity gets blown way too far out of proportion.
If your gun likes RL15, you'll never be disappointed. Besides, apps like shooter have fields for powder temperature variations. The calculator adjusts for temperature. For example, years ago I had a super sweet load with N540 which when I tested temp variation it worked out to 0.6'sec per degree. Entered into my calculator and it adjusted the MV up or down according to the current temperature.
IMHO, a lot of guys miss out on their sweetest load potential by having to have zero temperature sensitivity. Shoot what your gun likes and learn the ins and outs of it. You'll be happy that it shoots top notch. That's the whole point of practice and knowing your rifle right?