270 Winchester Magnum???

track

track

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I've been out twice to the gun range in the past two weeks, working on a super load for my 270 Win., and to achieve the goal of 3,300 fps combined with 1/2" accuracy........well it happened. Last year I received great results from the 270 win., Alliant 16 behind the 130 gr. Accubond. Velocity was 3,266 with 1/2" groups, however my goal was not met to achieve 3,300 fps plus. After conducting some recent research, there was information about Alliant #26 and increased velocities and accuracy, however nothing on the 130 gr. bullet, only the 150 gr. A PM to a Gun Nutz member for information on the 130 gr. combined with Alliant #26 concluded my search.
(Note:*** Thanks to Buckmastr for providing me load-data through Quickload***)

Here is some figures:

Custom 270 Winchester - E.M. Precision
Remington Action
Bob Jury Custom Barrel 27" 1-10 right twist
B&C Stock
Trigger Tech Trigger 1.5 lbs.
Swarovski 2-12x50
Weight: 9 lbs. 10 oz. with scope

First round of load data showed promise, however it required some fine tuning. I concluded that the powder loads of 61.0 grains with 1/10th of a grain increments may be the trick. Therefore, 61.0 to 61.7 were conducted and results are superb! As you can see in the photo that the 270 Win. out performed itself by reaching near velocities of the 270 WSM. accompanied with nice groups. Highest velocity group was 3,402, 3,418, 3,419 however resulted in loose primer pockets. Note the the white square, from edge to edge is 3/4", and not 1".

Data:
Hornady Brass
130 gr. Nosler Accubond
Fed. 210M
Alliant #26 61.5 gr.
.015 jump
Brass was weighed and outside neck-turned. Note that I did lose 8 brass, 3 blown primers and 5 very loose primer pockets.
https://imgur.com/a/ugtkxOe
 
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How many brass total did you shoot? You said you lost 8, just trying to figure out what sort of a percentage that would be.

Either way thats a spicy load! I'm only loading my 270win to 3050fps, and I've already split some necks after 3-4 loads...
 
Looks like that long barrel and that fancy new double base powder is really wringing out some serious performance. Good job!
 
Suther said:
How many brass total did you shoot? You said you lost 8, just trying to figure out what sort of a percentage that would be.

Either way thats a spicy load! I'm only loading my 270win to 3050fps, and I've already split some necks after 3-4 loads...
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I shot 30 brass in total. Reason for brass loss is that I wanted to push it until until pressure signs we're occurring. It is a spicy load, however the powder is most efficient, plus the rifle has a 27" barrel. With 61.0 grains to 61.6 there are no signs of pressure. At 61.7 gr. and onward, there is pressure.
 
You'll have to let us know if the primer pockets loosen after a few firings.

You're making me want to pick up some new powder for my 270, but I've got like 5lbs sitting here and I don't even use that rifle for hunting anymore! lol
 
track said:
Thanks in part from you. I just need a 160 B&C buck to find and test the load. Thanks again!
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Anytime.
I like how your goal was fast and weren't afraid to find the limit, with the experience to recognize the difference between your rifles max, and over max.
Good luck on the WT's.
 
Suther said:
You'll have to let us know if the primer pockets loosen after a few firings.

You're making me want to pick up some new powder for my 270, but I've got like 5lbs sitting here and I don't even use that rifle for hunting anymore! lol
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On the 61.7 gr. load I had a stiff bolt lift on all three shots, very possible that the primers are kaput. The other loads had normal bolt lift and no signs of pressure on the case head. Tomorrow morning I will give all the fired brass a good inspection. I will resize them and see how tight the pockets are. I really didn't mind wasting a few casings to achieve maximum potential. I have a 300 H&H that is almost complete from my gun maker (26" barrel) and will do the same.
 
I remember as a teenager asking a guy behind the counter at Russell Sports a question about a wildcat I had in mind. He literally laughed at me. Told me I ought to stick to something simple that I could handle. So I didn’t blow myself up. Now, I’ve loaded for and use wildcats and have yet to blow a primer. The guy behind the counter? Well......
 
Suther said:
You'll have to let us know if the primer pockets loosen after a few firings.

You're making me want to pick up some new powder for my 270, but I've got like 5lbs sitting here and I don't even use that rifle for hunting anymore! lol
Click to expand...

I conducted a thorough inspection on the 2nd firing of the brass and only found one (1) primer pocket that was snug, however not as tight as the remaining cases. What the hell, I tossed it. I purchased the brass at Cabela's, on sale for $60.00, no big loss. Primers were all flat, however no ejector marks on the head, nor any stiff bolt lift, except for the last load of 61.7 gr.
Couple of other things that I did when loading, I only trimmed to 2.535 instead of 2.530. I also used a long neck funnel to pour the powder, being that the loads were between 101% to 103%. A long neck funnel adds value to saving needed space in a case, as it has a uniform application of the powder; conventional short neck funnels lack this trait.
Another thing, initially I used Sako brass 1.5 years ago after the gun was built. I measured the Sako brass and compared it to the newly purchased Hornady. Hornady is 11 grains lighter than the Sako cases.
 
That's some kind of performance!
I used to push velocity like that but I guess I'm just old and cautious now.

My own 270 Win is pushing 130 grain bullet at 3150 fps with 7828 for .75 moa accuracy, but that's out of a 22 inch barrel and a plain old pre-64 M-70 Featherweight rifle. My 270 Wby pushes the 130 Acubond to 3550 fps out of a 26 inch barrel for .9 moa also using 7828. Neither load show any signs of high pressure and the case life is good.
 
chuck nelson said:
i remember as a teenager asking a guy behind the counter at russell sports a question about a wildcat i had in mind. He literally laughed at me. Told me i ought to stick to something simple that i could handle. So i didn’t blow myself up. Now, i’ve loaded for and use wildcats and have yet to blow a primer. The guy behind the counter? Well......
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ok and :confused: :) RJ
 
track said:
I conducted a thorough inspection on the 2nd firing of the brass and only found one (1) primer pocket that was snug, however not as tight as the remaining cases. What the hell, I tossed it. I purchased the brass at Cabela's, on sale for $60.00, no big loss. Primers were all flat, however no ejector marks on the head, nor any stiff bolt lift, except for the last load of 61.7 gr.
Couple of other things that I did when loading, I only trimmed to 2.535 instead of 2.530. I also used a long neck funnel to pour the powder, being that the loads were between 101% to 103%. A long neck funnel adds value to saving needed space in a case, as it has a uniform application of the powder; conventional short neck funnels lack this trait.
Another thing, initially I used Sako brass 1.5 years ago after the gun was built. I measured the Sako brass and compared it to the newly purchased Hornady. Hornady is 11 grains lighter than the Sako cases.
Click to expand...

Well this whole thing reminds me of something c-fbmi used to say, something along the lines of "who cares about annealing when the primer pocket is loose after 3 or 4 loads". Lol
 
Suther said:
Well this whole thing reminds me of something c-fbmi used to say, something along the lines of "who cares about annealing when the primer pocket is loose after 3 or 4 loads". Lol
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Brass cases for the 270 is relatively inexpensive, along with the 30-06; in comparison to other cartridge cases and brand names. Hell, once a bullet flies out of the barrel ($1.10 for each 270-130 gr. accubond) it cannot be reused; whereas, a brass case will last from 1 to 10 firings or more............it's bullets and powder that are the expensive components.
There is a journey that some find adventurous in the reloading world and willing to take baby-steps to push the envelope.;););)
 
I'll have to go back to review my records, but I believe it was the max load of RL22 listed in Barnes #1 manual that pushed a 130gr X to 3200fps out of the 22" barrel of my Remington Mountain Rifle. My friend had a Remington 721 and I started to work up the load but it was too hot for that rifle (using the questionable method of looking for flat primers and ejector marks).

Some barrels are faster than others. I bet that load would have been pretty darned close to 3300 with an extra 5" of barrel. In fact, I remember thinking about that load and how it would have performed out of a Browning 1885.
 
I would be concerned that you are overpressure without normal signs. I mean visual, bolt lift, along with fps spikes are all we use, not exactly completely telling of real pressure I don't think. I drive my 270 win 130's with RL22, my 22" barrel shows 3075fpsTha, but I get slight pressure indicators there, so have begun a new load.
In a 270 Win, do you get about 30fps per inch of barrel? That would bump my velocity 150fps, so 3225fps, the a powder change would increase that some more. Thats 200 fps more needed from a newer powder. Its possible but I would be very careful with going up there. What were the fps differences per increase of powder charge Track?
 
track said:
Brass cases for the 270 is relatively inexpensive, along with the 30-06; in comparison to other cartridge cases and brand names. Hell, once a bullet flies out of the barrel ($1.10 for each 270-130 gr. accubond) it cannot be reused; whereas, a brass case will last from 1 to 10 firings or more............it's bullets and powder that are the expensive components.
There is a journey that some find adventurous in the reloading world and willing to take baby-steps to push the envelope.;););)
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Oh I totally get it! I have a 7mm08 that I plan to try and squeeze as much out of as I can. This year I didn't get a range membership due to moving and then Covid, so I didn't have a good place for working up a load so I settled on a middle-of-the-road loading, 139gr GMX @2790, but once hunting season is over I'm going to look at driving this bullet faster, and if I can't get more speed from this bullet I'll be looking to switch to a bonded something-or-other, likely the 140AB but we'll see, I'm a sucker for a deal so if I see something else that tickles my fancy on sale I might go a different route.

Buckmastr was able to get 3300fps with a 120gr, if I can hit 3000fps with a 140gr I'll be laughing!
https://www.canadiangunnutz.com/forum/showthread.php/2020782-The-7mm-08-Remington-Magnum
 
Hard, short bullets can be driven faster then a monometal or berger. This is a good read.

https://www.shootingtimes.com/editorial/ammunition_st_practicalpressure_200809/100197

Most bullet jackets are a copper alloy called gilding metal, which is 95 percent copper and 5 percent tin (expressed 95/5). Some use a harder 90/10 alloy. Both are harder than pure copper and usually have lower frictional forces unless the pure copper jacket gets special processing.

Bullets with a higher percentage of light metals are longer, but where the light metal ends up can affect pressures, too. The big hitter here is jacket thickness. Varmint and match bullets usually wear relatively thin and untapered jacket walls. Big-game bullets will have thicker jackets to control expansion, and the jacket will be strongly tapered or profiled to put extra material in the critical shank area to increase retained weight after expansion.

Thinner jackets usually create higher pressure than thick ones. All bullets suffer the same dynamic forces when slammed by the propellant's pressure wave. The back of the bullet starts to move before the front, compressing the bullet parallel to its long axis. Were the bullet not confined inside a gun barrel, the jacket walls would bulge outward. Confinement does a funny thing; with pressure behind and frictional resistance ahead, the only way the bullet can deform is forward. The bearing surface lengthens at the expense of the nose length, and the bullet becomes more blunt. Elmer Keith called this deformation "slugging up" and liked it, as making any blunt bullet fit his idea of a proper big-game bullet. Additional increase of the bearing surface happens as the rifling engraves the bullet and displaces metal.

A stiffer jacket wall better resists this "slugging up" and can lower pressures. In standard .30-caliber Hot-Cor spitzers, the 165- and 180-grain versions use a heavier jacket than the 150-grainer, although the nose profile remains constant. If you plot the maximum charge weights across these three exact increments of bullet weight--150, 165, and 180--you see that the max load for the 165 is skewed toward the max charges for the 150. Were all three made with the same jacket, the max charge weights for the 165 would fall closer to the midpoint.
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