Home Forums Reloading Big Game Rifles Reloading data too low

my question is I looked in Lee second edition 140 gr 264 winchester magnum it list 60 gr of reloader 25 as max and velocity at 3,005. The load I'm working up now is 64 grains and my chrony showing 2,888 fps. whats going on? I know its not my chrony cause I checked it on my other loads and there all the same.

This could be because of a number of things.

Barrel length,
Ambient temp.
Primer differences, mfg. lot. ect.
Powder lot, although that is a big gap in weight,
Bore- loose or tight- neck too.

This would be why we start at reduced loads and work up, and why some guns can take it over mfg max rec, and others can't before seeing pressure signs.

this two cents may not even be worth two cents.

I also believe that seating the bullet out close to the lands of your rifle lowers pressure and therefor velocity.

Seating rifle bullets long increases pressure, increaingly so as you get close to the lands.

Hold on a second. Seating OUT decreases pressure, as long as you aren't jammed into the lands... correct? Greater area inside the case with the bullet seated longer=less pressure? Seating deep, less area inside the case=greater pressure?

and P= Higher MVs...correct?

You just gotta be careful because a max load off the lands is different than a max load in the lands.

Lee doesn't test any loads at all. The data in their book is merely copied from other sources. Assuming the listed load isn't a typo (which is NOT a safe assumption) the speed discrepancy is probably related to gun dimensions and/or bullet type. It isn't just bullet weight that matters.

Personally, when I got to the printed max and found a large velocity discrepancy, I would not have kept increasing the load. I'd have done some research first. I value my body parts.

Here's what quickload thinks. It appears there is something about your combo that is making it about 3% slower than predicted. Looks to me like there is lots of room to work up....do so watching this chart and using "hillbilly" reason.

Have to agree with Rocky on this. After Max + 4, I would go to a diffrent powder and bullet combo as Alliant also lists 60 as max. If ya dont value your body parts or the persons next to ya, then use Hillbilly Reasoning. IMO.

Swifty

Actually I'd trust the quickload data above. QL has no way of factoring in freebore and many of the newer guns and mag actions have plenty of it. That can be a quick 1-3% right there. Win brass could add to it also. Printed data for many cartridges today is crazy....especially 7 rem mag....and I'll add 264 win mag to my suspicions too.
Heck ...just checked my old brown imr pamphlet from many years ago....it says 65 grains 7828 is max with a 140. RE25 should be at least 2 grains stiffer than that.

Also checked an older hodgdon manual. It lists 68 grains h1000 as max with a 140 and actually the pressure of that load was listed as the mildest of all 140 grain loads. H1000 and re25 are pretty darn close in burn....if not a mirror image.

The only thing I've used the Lee manual for is recreational reading and starting loads with cast rifle bullet's. Get a manual by either the powder manufacture of better, the bullet manfacturer.

take a look here...
http://www.noslerreloading.com/phpBB2/viewtopic.php?f=4&t=18576&start=0

NO, not correct, and as always it's not that simple. And like most such topics its been done here over and over by folks who know more than I do but I read their stuff.

Best general discussion is Brownell's Pressure Factors in its multiple incarnations. Much of the other writings are take offs from Brownell's writings either in conjunction with Wolfe or previous professional articles.

Increased space behind the bullet tends to reduce pressure just as at the same time reduced space ahead of the bullet tends to increase pressure. And of course increased space ahead of the bullet tends to reduce pressure at the same time reduced space behind the bullet increases pressure - ceterus paribus.

For a great many people much of the time the increased space ahead of the bullet - think freebore or Weatherby style throating - dominates and so pressure (which is pretty hard to define CUP, LUP, Psi, Psia, peak or area under the curve) is reduced. But don't bet your rifle your eyes and your life on it.

My book shows a max load of 64grs with a yield of 2900+ fps. I'm thinking you need a quicker powder if you interested in max velocity.

Not according to the link at nosler reloading. AND...if you look at the ql chart about 68 grains is 100% fill...doesnt get better than that. As I said at the beginning of all the posts ...use the quickload data and work up. I have pretty good confidence 67-68 grains is gonna be full, safe speed.

Let me relate some notes I made in November of 2001. I was flying by the seat of my pants as there was absolutely no data available for this powder in the 264.

Winchester 70 classic w/ 26 inch factory barrel in 264.
Bullet: 140 partition
Primer: CCI 250
Powder: RL25
Brass: W-W

At 69 gr

1'st shot of group: 3045 fps,
2'nd shot: 3188 fps with a blown primer,
3'rd shot: 3309 fps


at 71 gr:
1'st shot 3231 fps
2'nd shot 3239 fps
3'rd shot 3239 fps

At first glance it might seem that 71 gr load would be the perfect. Except this was shot in on November 26 with an ambient temperature of about 40 degrees F. During the summer heat, 66 gr was well over max.

If I had been a little more knowledgeable at that time I would have recognized what the 69 gr load was telling me. The velocity increase with the second and third shots was due to the increase in barrel temperature as I fired the three shot group.

I have no idea why the same thing did not show up with the 71 gr load.

But I did, on several occasions, see the same increase in velocity and pressure as a group progressed when using RL25 with 140 gr bullets. Especially those with a long bearing surface like the partition.

Several other members of this board have related similar experiences with RL25 being extremely "spikey" in the 264 with heavy bullets.

I finally decided to consider 66 gr of RL25 a max in my rifle at 3090 fps. That worked fine in November, but when July came the 66 gr load started blowing primers.

The bottom line, I found RL25 to be very unpredictable and totally unsuitable in my rifle.

My rifle was much happier and so was I when I gave up on RL25 and went back to H1000.

09/01/97: H1000, CCI 250, and the 140 partition
65 gr: 3064 fps
66 gr: 3145 fps
67 gr: 3195 fps

In the 264, the length of the bearing surface of the bullet is quite critical to the load. See the difference with a shorter bearing surface when using the 140 Sierra spbt.

08/26/03: H1000, CCI 2050, 140 gr Sierra spbt

67 gr: 1'st shot 3015 fps, 2'nd shot 3004 fps.

This last load shot about .5 moa and became my standard load in the rifle.

I would also recommend one try Magnum if looking for top velocity in the 264.

05/06/06 Ramshot Magnum, CCI 250 primer, 140 gr Sierra spbt
66.0 gr: 2898 fps
67.0 gr: 2951 fps
68.0 gr: 2991 fps
69.5 gr: 3043 fps
71.0 gr: 3087 fps

My barrel was pretty well shot out by the time I ran these loads with Magnum. It would still group the first three into 3/4 of an inch, but #4 and #5 would open the group up to over two inches and it got worse from there until the bore was scrubbed free of copper again.

The rifle now wears a new 27 inch Pac-nor 1 turn in 8" barrel. I have worked up some loads with the 130 gr Accubond and H1000. I do not think H1000 is going to do what I want in this barrel with this bullet.

Magnum is next on the list to try.

Wow....interesting stuff. Spikey would appear to be an understatement for some of those results.

What length barrel does your rifle have and what was the temperature when you were chrongraphing your loads.

Have same problem with my 7MM Rem Mag, With 160gr or 175gr
bullets. Powder with most problem is RL22 and RL25. My Model
70 has 24" barrel. H4831SC has speeds closer to advertised.
Going back to recheck IMR 7828SC. I,m using 3.320 OAL as
magazine limits length. All other rifles I have Chrongraph
to advertised speeds.