Powder max on .270 Winchester

[James Pearson]

Hey guys, I've taken my 22" barreled .270 to 46.8gr of IMR 4064 chronographing 2800+/- a few FPS. Book max is 46.1 with 130gr bullets and 45gr with 150gr bullets. My tests have all been on 95+ degree days, and I'm just starting to see some flattening of primers with easy bolt lift. 3/4 MOA
Should I push this load any further?

 

[aushunter1]

.7gr isn't that much over max, I have on occasions gone up to 1gr over as long as I have worked up the load properly & the pressure signs aren't significant.

But in saying that, no one else can tell you something will be safe in your rifle!!

Still a lot of the time rather than increasing powder charge I do also look at other methods of fine tuning a load like changing the seating depth in 5/10/15thou & out 5 thou off the lands.
5 thou off the lands is the closest I will go in a hunting rifle as I done want to chance a round accidently not chambering OR leaving the projectile in the chamber if I need to extract the round.

I start all my LD at 10th off the lands & once I find a half decent charge between the min/max I start playing with the CBTO.

 

[johnnyk]

Welcome to LR Hunting James!
I just went to Hodgdon's website and they list 47.3-47.5 as max for IMR4064 with 130gn class bullets. The 150's were as you stated; 45.0gn.
If it were me, I'd attempt to push on to the upper range (47.5), as long as pressure didn't show up.
Remember with the reloading guides or any info listed; the information was more than likely safe in THAT rifle, in those conditions, and is only a guide. YMMV as they say. You could pressure out earlier or go a little past their range. Go slow looking for pressure signs.

 

[CVCOBRA1]

Brass thickness and case volume can turn that into a grenade...take care.

 

[aushunter1]

Brass thickness and case volume can turn that into a grenade...take care.

True, anything is possible in reloading.
But if that was the case the evidence would have presented itself during the working up period.

It a pretty simple thing though what your say, if you work up to a load with one type of brass then don't expect when changing brass to another brand it wont affect the result.

When doing anything with this pass time you should err on the side of caution at all times!

 

[James Pearson]

I'm sticking with Hornady brass. Not competing, just want a good low ES round with the 145-ELD-X's, on the upper end of the spectrum if possible.
I just broke in another .270 and going to run FPS trials in it today.

The first gun seems to not like that bullet with any combination so far. So the new gun I'm going to trial Hornady brass, CCI 250 primers, and IMR 4064, IMR 4831, and H-1000. All once fired brass, bumped .002, CBTO @ 2.755 (chamber is 2.775), case trimmed to 2.533.

Also bought a new chrony, so now I can run 2 in tandem and verify results better. I'll update y'all later and thanks for the valuable information.

 

[James Pearson]

Sorry all, I should have mentioned I'm loading for 145gr ELD-X bullets in my initial post, and no load books I've found have info on that one. I probably should have called Hornady 1st off!

 

[Capt RB]

The 4064 isn't optimum for the 270. H4831 was the standard for the 130 7828 is very similar to the original 4831 surplus. I'm now running Rl26 with the 140 gamechanger. It shoots best at 3140 with sub 10fps es usually 3 with sd of 1. It will shoot sub moa to 700yds mostly sub 1/2 moa when I drive it right. This in a stock vangard sans timney trigger.
This is fed brass 9 1/2m trimmed pockets uniformed necks seated so the boatail is at the neck shoulder juncture. which is .018 off the lands. In winny brass it need more powder and doesn't give me the as good of deviation at 12es.
I'd look for some better brass than the hornady. RWS if you find it norma and nosler are quite good and if you prep/sort winny and fed will produce very uniform loads also

 

[bearcat2]

I've only used 4064 to load min loads for my 9 year old brother-in-law to shoot. Not even sure what I originally bought the powder for now, but I apparently didn't care for it and since I had an almost full jug laying around it seemed like a good powder for a 9 year old to shoot daddy's gun and ring steel at a hundred yards (occasionally) without ripping his shoulder off and developing a flinch.
RE-22 always shot great in every 270 I loaded for but it is temp sensitive (I've had excellent accuracy out of all the reloader powders I've used in different calibers, but I've also had some issues at zero to subzero temperatures so am veering away from them in any gun that might be used in those temps) 7828 SSC does well also. Just remember DON'T use load data for 7828 long cut. You WILL have pressure signs! (don't ask me how I know this, I'm an idiot) Ramshot also makes their Magnum powder which is a hot powder (over 3100 with 150's out of my 270) and a joy to use on the reloading bench, I've never used another rifle powder that meters so evenly. I've had good accuracy with it in most guns I've tried it in.

I've never tried the ELDX bullets, had poor luck with Hornady big game bullets in the rifles I've tried them in (varmint and pistol bullets I've had excellent luck with) if you want an expensive bullet with a poor bc, but that is absolutely devastating on game and superbly accurate in every 270 I've ever fed it to, I always recommend Grand Slams for a 270. I don't always shoot them because there are other bullets that do a perfectly good job, but they are the best bullet I've ever tried in a 270 and when performance and accuracy are really important and I'm packing a 270 that's what I'm feeding it

 

[entoptics]

I concur on 4064 being too fast for the 270.

I was getting ~2880 fps with 145 ELDX and ~59 gr of H1000 in my 22" Marlin without any pressure issues. Unfortunately, the ELDX patterns like a 12 gauge in my rifle.

140 Nosler Accubonds shoot pretty decent, and those I'm pushing right around 2980, again with H1000.

I personally wouldn't recommend pushing a load past "flattening of primers". Instead, I'd suggest switching to a slower powder. You'll get more speed with less pressure. I'd probably go no faster than H/IMR 4350, and more likely something as slow as H1000, RL22, or 4831.

270 may not seem like it, but it's approaching "magnum" overbore, and needs a slowish powder to really shine.

 

[Gary in MD]

As suggested, there are too many powders that are better in the 270 Winchester. H4831 and Rl22 have shot accurately with good speed for me, also 4350.
Gary

 

[James Pearson]

I concur on 4064 being too fast for the 270.

I was getting ~2880 fps with 145 ELDX and ~59 gr of H1000 in my 22" Marlin without any pressure issues. Unfortunately, the ELDX patterns like a 12 gauge in my rifle.

140 Nosler Accubonds shoot pretty decent, and those I'm pushing right around 2980, again with H1000.

I personally wouldn't recommend pushing a load past "flattening of primers". Instead, I'd suggest switching to a slower powder. You'll get more speed with less pressure. I'd probably go no faster than H/IMR 4350, and more likely something as slow as H1000, RL22, or 4831.

270 may not seem like it, but it's approaching "magnum" overbore, and needs a slowish powder to really shine.

That Marlin is tough! I have one and it takes a lot to get a stiff bolt. I'm going to run some in the H1000 and see what I get. I'm testing a mossberg patriot, it appears to like the 145's. Shot between two test runs if 11 rounds each today, 4064 and 4831. 2gr increments and the entire groups in both were 2.5". Of course I'm shooting for FPS not groups but I had several within 4grains in both that we're good indicators, but I never got close to s high pressure signature.

Gonna keep throwing them down range until we see a good one, or we'll do something different!

 

[Chino Tom]

I've been working up a load for my Tikka 270 for the 145 ELD-x. I had great success
with the ELD-x in my 260 Rem for the last two years. My 270 liked RL22 with a 150 Partition but not so much with the 145 ELD-x. Good velocity, but not consistent accuracy. I had some RL17 and have had much better luck with it. 54.5 grains
of RL17, Federal Match primers and Nosler brass, 3.34 COAL (magazine limit) results
in repeatable 3000 fps and .75 MOA or less. One note on the Nosler Brass, I'm on the 4th reload on this lot and had my first case head separation. Out of the 50 pieces about 10 are showing stress lines. Not sure if I should can the remaining cases.
Used new brass for this season's upcoming hunts.

 

[CVCOBRA1]

If I had to question that brass it would be gone. Esp if it is going to be used in a hunting situation. Might load some for to foul the barrel at the bench. But mark them well.