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Discussion Starter #1
I shot a new load yesterday IMR 4064 with 95 Gr BT Noslers my load was 36.5 at 2.690 group size 3 shot 3/4"
I was very surprise to gain about 10" in height
I can load the same bullet with IMR 4350 and be about 1" high any reason for the difference in height comparing the 2 powder with the same bullet.
I was thinking in dropping the IMR 4064 1.5 grains down and try a longer COAL like 2 740 should get me about 20 thou off the lands.any info would help
 

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Your 4064 load is the same load I use, with 100 gr Hornady for the past 40 years. very accurate out of my Sako.

If it is a hunting rifle, with a 3/4" group, I'd not change anything, except the scope adjustments.
 

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LONEWOLF5347 said:
I shot a new load yesterday IMR 4064 with 95 Gr BT Noslers my load was 36.5 at 2.690 group size 3 shot 3/4"
I was very surprise to gain about 10" in height
I can load the same bullet with IMR 4350 and be about 1" high any reason for the difference in height comparing the 2 powder with the same bullet.
I was thinking in dropping the IMR 4064 1.5 grains down and try a longer COAL like 2 740 should get me about 20 thou off the lands.any info would help
What do you mean you gained 10 inches in height? On the group? That's odd.

The load data below is from the IMR website. Although not the same bullet, it is the same weight. Your load of 36.5 grns of 4064 is about 2967 FPS.

You didnt mention your charge weight in 4350, but the two listed are both higher provide 2800-3000 fps. That shouldn't create too much of a differance in elevation at 100 yds.


95 GR. NOS PART IMR IMR 4350 .243" 2.650" 38.0 2792 43,200 CUP 41.8 2993 50,200 CUP


95 GR. NOS PART IMR IMR 4064 .243" 2.650" 33.0 2745 43,500 CUP 36.5 2967 51,100 CUP
 

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Was your rest position the same? Could you have had the barrel resting on the bags / rest?
 

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I have seen that many times. It is nothing to worry about as long as your loads shoot consistently.

Your rifle probably has a light contour barrel. And POI has alot to do with barrel harmonics. You probaly just found the exact loads where one leaves the barrel at the top of the Sine wave and the other leaves at the bottom of the Sine wave. After all the main reason for a heavy varmint barrel is to stiffen the barrel and reduce the harmonics.

Just think of it like the Tacoma Narrows Bridge in Washigton State that vibrated apart. Did you ever see that video??

Your barrel is also probably free floated. And free floated barrels can cause this. This point of impact change is the main reason why most custom rifles were bedded at the tip of the stock-this is done to reduce the harmonics in a light barrel. But it seems to be a lost art among smiths. Tom.
 

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Discussion Starter #7
I use the set up as far as benched forearm same hand pressure,could be the full free floated barrel.I know the barrel has a long throat.I can chamber 2.800 bullet and brass with out any problems closing the single action.
I may run a load test on the lower end of the chart and run the bullet 30 thou off the lands.
 

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LONEWOLF5347 said:
4350 used 40.9 grains
yep 10" high on target
So you are shooting 2 loads, both with the exact same bullet, and likely less than 25 fps differance in muzzle velocity, and one is 10" higher than the other??

I would like to see you shoot alternating shots with each load, allow cooling in between each shot, and see if you get two distinctive patterns 10 inches apart.

I understand the harmonics, but that just doesn't seem right to me.
 

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Discussion Starter #9
I am heading out tomorrow I change my set up I am going to try to use the start min: load but get more into the lands by about 30 thou: and see how the gun shoots.
I tested a lot of different loads but more on the high end.
I know my chamber has a long throat my 95 noslers BT will close on 2.820 I am going to try 2.745
I like to ask a question seem the 243 cal. if a finicky cal. I find my brass will stretch the shoulder to about .010 longer after the case is fired:any reason for the excesses case stretch?I full length resize on the single action and push the shoulder back only enough until .001 can be pulled out from the breech face and barrel wit the round chambered..
 

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Discussion Starter #10
I can remove the .001 but have to go deeper on the resizing die to get a .000 tolerance between the barrel face and breech but I think that will give me a little excess head space
 

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LONEWOLF5347 said:
I find my brass will stretch the shoulder to about .010 longer after the case is fired:any reason for the excesses case stretch?
In this thread, you never stated what gun you are using. My Encore 30-06 blows the shoulder out 10-11 thousandths. That's a probelm when resizing, can get them back down to be used in my bolt action after fired in the Encore. It's because of the gap between the barrel and breech plate.
 

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I use 4064 in most of my rifles. The same thing happened to me a few years ago, but oppisite in my 30-06. It is sighted in for 3" high at a hundred yards when useing the 4064. everyone said it would do better with 4350, it shot 6" low( 9" difference) so I stayed with the 4064. Have no idea why.
 

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LoneWolf, I am in Japan, and my Encore is in PA. I will measure the gap when I get home next.

When I chamber a factory round, it fits flush in the barrel, no protrusion. But once I fire and reload a round, it does stick back some. I think HOGGHEAD posted in another thread that typical closed-breach gaps on Encores are between .001 and .004 inches.

Here is a spreadsheet from my last day at the range. I was having trouble bumping shoulders back in my reloading, and in fact had suffered about a 8 stuck cases. I was trying to reload Encore brass so it could be fired in my bolt again. I learned the hard way that once it's fired in the Encore, its useless for my bolt gun.

Each cartridge was measured to the shoulder immediately before and after the shot, and recorded for shoulder blow-out. By the way, the numbers themselves are meaningless, as the attachment on the caliper adds a lot. The differance between the two measurements are the important numbers.

First spread sheet is in shot order. Second is grouped by rifle (Encore and Rem 700 RMEF XCR)

You can see I shot three-shot groups, ands allowed time in between, to prevent overheating.






All shots were with Remington CoreLokt ammo, except #16, which was a 700 reload, and 19, which was an Encore reload. Notice I was able to get the shoulder back to factory on the 700, but not on the Encore.

You will notice that on average, the Encore is doubling the shoulder blow out of the 700.

Also, if you notice the one in blue, I actually had a hard time getting the rifle to close on that shot, and it is actually knocked back after firing. Thought that was interesting.

Hope this helps a little. I learned a lot from the experience, and it led me to ask some questions, which some guys on here provided really good answers to.
 

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John are you FL resizing those? are they factory?
Seems that neck sizing would keep you cases from "growing" and keep the brass from working?
 
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