264 Win Mag Powder & 140gr Accubonds?

[Wookie316]

264 Win Mag Powder & 140gr Accubonds & seating depth?

This beauty needs to perform to it's potential since my 7mm Rem Mag will push a 140gr @ 3350 FPS with RL22.

It is a 26" 1-8 twist.

So far I am getting my best results with 64.5gr RL25, but that puts me in the 3100 FPS range. I used to get 3250 FPS easy with another 264 WM years ago with H870. But I don't have any H870 anymore When I ran out of H870 with that rifle I used 64gr RL25 @3090 FPS in that one with good accuracy.

Groups seem to open up @ 65gr RL25

I am 10 thousandths off the lands

So you 264 fans need to help me out. I am especially interested to see if anyone is using Retumbo or US869 with favorable results.

 

[JYuke]

You will be lucky to get 3250 with 140 gr bullets.

I load H 4350 for mine with 140 gr Nos-parts to 3200..

The bigger case always wins,,you will not match your 7mm for velocity with the same wieght

3350 seems real hot for a 7mm rem mag, the 7 Rum chrons at 3400-50 avg with 90-95 grains of powder in a 26 inch barrel.

 

[Wookie316]

I plan to back down a bit on the 7mm as that is a bit warm.

If I can hit 3200 FPS with Retumbo or US869 & good accuracy I'll be happy.

 

[RT2506]

My 264 Win mag has a 27 3/4" barrel. I have not tried the 140 AB but I have found that 66.5 grs Retumbo , CCI 250, WW case reformed from a 7mm Rem. mag case, 130 AB ten thousands off the lands gives me 3350 fps and shoots in the .4's at 100 yards. I have not been able to try it at longer ranges yet. I just got the rifle a while back and have not had much time to work wih it. I agree with the others I don't think you will be able to get 3400 fps with the 140's.

 

[Wookie316]

I know 3400 FPS is not possible, but 3250 FPS should be easy with the right powder. My last one did that.

 

[JYuke]

I think you can get it...

I have seen 3400 in a 7mm rem mag before at the range from a browning high wall with H4831

 

[Wookie316]

I think you can get it...

I have seen 3400 in a 7mm rem mag before at the range from a browning high wall with H4831

7mm Rem Mag yes, 3418 FPS was the highest I got out of mine on Sunday.

264 WM NO. I think even with a 26" barrel 3250 FPS will be close to max.

 

[Wookie316]

Well I am going in the wrong direction I have gone to worse not to better. My rifle does not like Retumbo at all. Started at 64gr & worked up to 66gr. Definite pressure signs at 66gr. 64gr was the most accurate, but is was only a 1 1/2 group with speed just under 3100 FPS. 66gr groups were in the 4" range I did like the speed there (3180 FPS), but with pressure signs & 4" groups that's not going to work.

The barrel seems to be very dirty this time with Retumbo powder. The RL25 was much cleaner. The first 2 patches were black!

I can get some US869 on the 18th of this month, but I am not sure if that will help?

On a + side the 7mm I built for Dad shot a 1/2 inch group with 67gr RL22 @3250 FPS. So that rifle is ready to go. Maybe I'll give him the 264 & keep the 7mm for myself (LOL)!!!

 

[Long Time Long Ranger]

7828 has always shot very well for me with top velocity out of my 264 win mags. 3350 is usually max out of a 7 rem mag with the 140. The 264 win mag is a 7 rem mag necked to 264. When you go down in caliber you go down in velocity with the same weight bullet making 3250 max in the 264 but with a higher BC.

 

[Wookie316]

So after a few trips to the range I am finding the 64.5gr of RL25 seems to be my best accuracy/speed combo. I am at a average of 3116 FPS.

I fired 7 consecutive rounds with the lowest @ 3102 FPS & 3126 FPS being the highest. All 7 rounds were just over a MOA, so I am thinking seating depth is my next step. I know I am just off the lands right now. I don't have a competition seater, so I don't know exactly how far off I am?

What is the best way to play with seating depth to find the sweet spot & tighten your groups up?

On another note a few mentioned trying 130gr bullets which I have also. I found 64gr RL25 to be the best with those as well. Average speed was 3123 FPS. These also grouped in almost exact POI as the 140's right around a MOA. Stepping up to 65gr RL25 caused groups to open up considerably (just like the 140's with 65gr) & averaged 3189 FPS with a top speed of 3211 FPS.

It's looking like the 3100 FPS range is where this rifle likes to shoot the best?

So advice on how to further tighten these groups would be appreciated.

Thanks.

 

[Wookie316]

264 Win Mag Throat question?

Question for 6.5mm 264 shooters. Right now I am @ 3.440 COL with a 130/140gr Accubond & could go all the way out to 3.600 in the mag box & still feed properly. Being the 6.5mm is such a long bullet, would I be at an advantage having the barrel throated longer to seat the bullet out farther. These are the bullets I plan to shoot, & I hope to use US869 powder when I get my hands on some. I have to make a trip to my smith next week & he say he has time to throat the barrel. I am wondering if it would be $ well spent.

Thanks.

 

[Wookie316]

Managed to track down a pound of H870, any idea where to start with a 140gr Accubond?

 

[Wookie316]

H870 smartened it up

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 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 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.

 

[Wookie316]

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