Home Forums Reloading Big Game Rifles 270 Win H4895 Reduced Load

I'm going to load H4895 reduced 130-gr load for my 270 Win. Target velocity is ~2200 fps.

Hodgdon's "60% of Max" rule, applied to 270 130-gr H4895 Max 45.0 grs, yields 27.0 grs for minimum safe load, but doesn't indicate what velocity I might expect.

Extrapolating between Hodgdon's starting load velocity and max load velocity, linearly (I know, a useless exercise at best!), I wonder if 29.5 grs H4895 won't yield closer to 2200 fps?

Question: Has anyone out there clocked their reduced H4895 loads in a 270 Win?

[Note: Not interested in Trail Boss or any other powder besides H4895, thanks - in advance!]

In the Lyman #47 33 grains of 4895 yields 2007 fps with a 150 cast bullet, so your close. Somewhere in the 32-36 gr. range should work for the 130.

I used 40 grs of 3031 for a reduced load with 120 gr. bullets at about 2,500 fps. Can't find my data on the 4895 load.

You will get closer extrapolating downward from Hodgdon's published data points.

Not just because they are published, but because the pressure will be more in the operating range you need. Nearer to the top a few grains will often make a big difference in pressure. 60% is way down the scale.

4895 is predictably linear within reason. You can use graph paper and draw the trend lines for velocity and pressure.

I keep my min loads around 40k psi. 4895 burns well in that range, and you need enough powder in the case to ignite consistently.

The 29.5 grs is the result of a simple linear velocity trend extrapolation - but arithmetically (sans graph paper). That extrapolation tells me that I have to dip 15.5 grs below (or to 66% of) max charge to reach 2200 fps.

Doing the same for a pressure target of 40,000 CUP yields only a 5.25 grs drop below max charge. So there is a roughly 3:1 difference in slope (using those two end points) between the pressure and velocity linear trends! Not surprising, since eyeballing Hodgdon's data shows starting charge only 3 grs below max charge dropped pressure from 51,000 all the way down to 44,000.

I have loaded a youth load for a friend. In his 270 Win, with 130 grain Hornady SP bullet, 22 inch barrel, 36.0 grs of H4895, WLR primers and Win. brass, gives a chronograph velocity of 2240fps with good accuracy. Hope this helps as a starting point.

If you load 60% of the powder,will you get 60% of the velocity? Just a thought.

Fairly close to it with single base powders.

Thanks! That's exactly what I was looking for. My M77 has a 22-in barrel, I use WLR primers, only difference will be Hornady cases, but this will save me time and be plenty close enough for my purpose.

H4895 is a really useful powder. I use it a lot. 44 grains with a 150 grain is what I use in 308's. I use it for my M-1 loads also.

Update:

Upon trusted advice, and after reading Richard Lee's treatise on reduced loads (using Lee's published "1-gr reduction" values), I have determined that IMR 4895 (of which I have plenty) will work as well as H4895 for reduced loads.

There's nothing magical about H4895, it's just the only powder for which Hodgdon took pains to publish reduced load data for, and is arguably one of the best powders for that. (FWIW many other powders may be safely reduced loaded to 60% of max, using Lee's published data as a guide.)

Update:

From Lee's "1-gr reduction" values for IMR 4895 in 270 Winchester, I ran through the algorithm and arrived at 30.5 grains IMR 4895 (130-gr bullet) to target ~2200 fps. The max load to reduce from was 46.9 grs (2957 fps), so 30.5 was 65% of max charge. Yesterday I shot 10 loads, and clocked 5 of them, which averaged 1943 fps, or ~ a 66% of max velocity of 2957 fps.

So the Lee approach overshot the velocity reduction. Of course there are many other variables like powder lot, seating depth, primer, temperature, chamber/bore dimensions, case capacity, etc.

Using my results, I estimate that 34-35 grs IMR 4895 will get me closer to 2200 fps. TBC. (I.e. close to 75% max charge to get close to 75% max velocity, which is what some chaps here have said all along, that the charge/velocity ratio was near 1/1 or linear.)

You were close! I'm using IMR not Hodgdon, but I estimate 34-35 grs after my first swag, and you suggested 36 grs for H4895.

For what it may be worth Brian....

I disassembled the Managed Recoil version of Remington's 270...IIRC it was a 130 bullet, but the powder charge was 36 grains of IMR 4198.... which was suppose to give an MV in the 2500 fps range...

for 2200 fps, you should be in the ball park with 35 grains or so of IMR 4895....

Thanks, Seafire.

Update:

Upped the charge from 30.5 to 35.0 gr IMR 4895. Ten shots averaged 2130 fps, fastest was 2186, ES of 95.

So 4.5 grains more powder averaged 188 fps faster, but still well below 2200.

Dear Seafire,

I'm looking for reduced loads for .270 Winchester with 130 gr bullets, 1800-2400 fps range for target shooting up to 100 yd deer hunting in PA woods. Can you help?

Also, can you educate me how you determined 4198 was used in this load? I'd like to determine similar for Remington factory 7mm-08 and .30-06.

If you'd like, you can pm at jsmvmdaol.com until I get authorized as a new user. I'm not here as much as I should be so might miss your post.

Thanks a million! Jack from PA

Jack,

my determination of Rem Managed Recoil using IMR 4198, came from two sources....and if It isn't 4198, its something else that has the same burn rate range.....

First was chronographing one... then took the velocity and bullet weight into account... and then checked on some of the older reload data around for 4198 in a 270...36 grains of 4198 was listed as 2500 fps...

I use a lot of 4198 loads of 30 grains in calibers from 243 to 30/06 for lower recoil for kids to use...with 30 grains of 4198 in a 270 with a 130 gr bullet runs right in the 2200 to 2250 fps range... which sorta verifies the fact that 6 grains more would yield about the 300 fps more...