The 264 WM grew up. Enter the 6.5mm - 300 Win Mag

H870 smartened it up :D

I was able to get a pound of H870 for testing. Things are looking up.
Had to go to the gunsmith to have a trigger issue resolved which turned out to be a weak return spring. I also had him put a recessed crown on it & throat it 45 thousandths longer. Now the bullet seats much nicer. I am at a COL of 3.495 with a 140gr Accubond.

I loaded new Win brass with 215F primers. I started at 73gr H870 & went up to 75gr H870 with the 140gr Accubonds.

I only loaded the 130gr Accubonds at 75gr H870

I also tried some 130gr Accubonds with 62gr IMR7828. Speed was OK, groups sucked & signs of pressure were showing.

The 140gr @ 73gr were kind of all over the page.

The 140gr @ 74gr did the vertical string thing :confused: This made no sense what soever. The one is a definite pull, but the other 4 got higher every shot? Weird? Speed averaged 3179 FPS. This was also shot before the other groups. Any ideas on that group?

The 130gr @ 75gr grouped very well. There is 3 shots in that cluster at the top :eek: This group got me excited. Average speed was 3254. High 3265 Low 3248.

The last group was the 140gr @ 75gr. The one is a definite pull. the average speed was 3206. High 3216 Low 3197.

Looking like 75gr is the magic #. I'll play with the seating depth a bit. I am 12 thousandths off the lands currently.

Being H870 is discontinued I am hoping I can duplicate these groups with US869 when I get some this weekend. :)

The frustration is now starting to lift. I am now seeing the FPS & grouping I was looking for. A 264 with the right combo can shine.
 
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Retumbo yes, it did not like it at all. Started @ 64gr & went to 66gr . 1 1/2" group @ 64gr & speed lower than my RL25 testing. By the time I go to 66gr I was seeing signs of pressure & 4" groups.

Have not tried N170, but would be curious to see what it would do?
 
US869 is TOO slow for the 264 IMO.

Well I got back from the Gun Show with a fresh pound of US869 to try in the 264. First off, I have no photos to post as it didn't really knock my socks off & there is nothing new to see :(

Loaded 140gr Accubonds starting at 75gr up to 78gr & 5 rounds of 130gr Accubonds at 77gr.

Bottom line is speed was slow & accuracy was average. FPS spreads were decent though. Here is how it broke down

140gr Accubonds:
75gr only shot 1 @ 2984 FPS
76gr FPS averaged 3047 FPS Low 3040 High 3053. 3 shots with 2 touching (almost on top each other) grouped 3/4" & 2 other shots were touching, but about 2" from the group? Not sure if it was me or not?
77gr only got 2 shots to read. 1 @ 3099 & the other @ 3081. Shot a nice little 3/4" triangle, but had one shot about 1" higher & one about 2" to the right? Again not sure if it was me, it was windy today & busy at the range.
78gr is TOO much in my rifle. First one was a tight extraction & read 3140 FPS & the second was a VERY tight extraction & did not register on the Chrony. I brought the rest home to be pulled.

130gr Accubonds
FPS averaged 3106 FPS. Low 3072 High 3124 FPS. No accuracy at all. 5 shots in a 2" group.

I have read a few posts claiming US869 to be TOO slow for the 264. I will add my name to that list. If 3050 FPS was my goal, I can reach that with a lot less RL22 & the same accuracy.

I had high hopes for US869, but it just didn't make the mark. Oh Why Oh Why did they discontinue H870 :(

It is looking like once my H870 is gone (which won't be long) I'll have to tweak my RL25 load as it is doing quite nice in that 3100 FPS range.

Just thought I'd post this info for those 264 shooters since there isn't much data with new powders & the 264 :(
 
I had the exact same result with US869...Im sure there a few pounds of H870 hiding here and there..I have part can that will never be used and Im sure there are plenty of others that some with no use for it.

All is not lost with US869, I did find use for that powder after all.....7mm STW with 160 gr. accubonds...3300 fps, I thought it was a bit fast but I cant see any pressure signs and only 1 gr over hodgon max.
 
Wookie316. Another powder that is basically a dead ringer for H870, but in extruded form is [now also obsolete] H5010. I burned several pounds in about 5 - 264 Win Mags and always had super results with it. If there is any around, you might want to try it for the heck of it. Regards, Eagleye.
 
Very happy with the results.

For those who have been following my 264 WM issues, I opted to shorten it 1 1/2" to finish at 24 1/2" & open it up to a 6.5mm - 300 Win Mag. This wildcat is a very simple neck size with no fire forming required. That helped my decision quite a bit.

_JAY6009.jpg


Well it was -31 yesterday morning when I put it to paper. It was our last day of Whitetail season, so I wanted to load it with something accurate & fast enough so I could just put it to paper & continue on my day hunting.

I pondered where to load this thing at. I finally decided on 79gr H870. Why? I figured this would be enough powder to get me some speed & not get me in trouble. I also neck sized & loaded the two test rounds fired by my gunsmith. I wanted to see if these rounds were going to have a once fired issue again like I was getting with the 264 WM. Both rounds fired & extracted no problem. Here is what it did. Keep in mind it was -31 & the shooter may have rushed a bit. Mind you I do like what I see :)

Top shell was the 2nd shot after a horizontal & vertical adjustment. The first shot hit the target beside this one (not shown). The next 2 were fired after another adjustment & the last three were after another adjustment. I am not sure why the rifle wandered a bit back to the left? There was no wind it was just bloody cold. After the 3 shot group I made one more adjustment to the right & fired at the other target (not shown) & it was dead center of the top dot. Good enough to go hunting. Man this beauty has a muzzle flash though :)

The chrony did not work in the AM as there wasn't enough light, but I did set it up when the sun poked out for 1 cold bore shot. 15 feet from the muzzle gave me 3274 FPS ;) Judging by the group I think I may be pretty close with my load. Some tweaking when it is warmer out & we should be in the ballpark.
I did neck size one fired round when I got home and put a primer in the case. Primer pocket still very nice & tight. Not like some reloads I have done over the years ;) The re-sized shell goes back in the chamber like nothing :) So all & all I'd say I'm happy :)

Here is the load details

Hornady 300 WM brass necked to 264 & trimmed to 2.610
Federal 215M Primer
79gr H870
140gr Accubond
COL 3.530. 20 thousandths off the lands.
.295 neck before firing & .298 neck after firing.
.514 at the expansion ring.

Nothing to shoot at yesterday, not even a coyote :( Had one doe tag left, but in -31 weather it was going to have to be big to get my hands dirty. :D
 
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Very nice!

So you shortened the barrel 1 1/2", and added 50 fps MV while lowering pressure? Sounds like a winner. Of course we haven't heard the end of it - I imagine you could hit 3350 fps with a 140gr and still be at manageable and accurate pressures.

Of course it's not "efficient" because it's so "overbore" and your accuracy will degrade after 1000 shots (and lions and tigers and bears oh my!). I suppose it's worth it to you to spend another nickel a shot and have to rebarrel in 20 years or so?
 
All I do on mine is neck size with a 6.5 Hornady neck sizer .If it's been fired a few times I partial resize with a 264 win mag.Use the 264 bullet seater and you are good to go.Unfortunately all my load notes got wrecked in a flood so I get to start over.Wookie as I told you at Senlac All I used was 7828.
Rich
 
I form the brass like Wookie, with a 264 WM F/L Sizer. Neck sizing is done with a 6.5/300 WSM F/L Sizer (the universal 6.5mm Neck Sizer), or you could partial F/L size with the 264 die, except that the neck is short to start with, so you end up resizing practically the whole case to get enough of the neck sized to provide good grip on the bullet. When that gets tough to chamber, you go back to the 264 WM F/L Sizer.

I bet that puppy could get 85 gr bullets to 4000 fps with a heavy load of H4831 (~78-79 grs). :D
 
I use the same procedure for a 6.5 STW (and a 257 STW, now that I think of it). - dan

....and I'll use it again when I get my 6.5mm RUM built. I have the 7mm RUM brass and dies - just looking for a Long Action Savage (now discontinued) to build it on. Mysticplayer can get me a 28"+ barrel pre-chambered in it. 140's at 3500 should be easy. :eek:
 
I have the Redding deluxe 264 WM set. I use the neck sizer die to size the neck. I just backed off & adjusted the die accordingly for the bigger 300 WM case. I used the same method for the seating die. All seems to work just fine.
 
Well, looking at my Sako it appears to have a Sammi throat...I guess I'll see what kind of velocities it gives. What's everybody think, would getting the throat done hurt any future value? It's a Finnbear, might make it more valuable:D
 
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