IMR 4895 for 7mm Hornady?

A

Alpsman

Inactive
Hello Fine People,

Very short of powder and bullets. Friend gave me a full box of 139gr Hornady BTSP Interlock. I have about 4lbs of IMR 4895, short on all other powders - need to load and sight in for the freezer.

Does anyone have load data for this bullet and powder? I know it probably is not the optimal load for sure. Shooting out of a Ruger MK11 7mm Rem Mag.

Any assistance is much appreciated!


Thank you all in advance,

Alpsman
 
The only load source I can find is in quick load (not sure if your familiar with the software). I don't really like using it as a SOLE reference, but I have found it to be pretty accurate in terms of velocities, given the whole garbage in, garbage out mantra. It's computer simulations, so take this with a very cautious grain of salt. Sure, it lists pressure, but I have no way to verify any of it.

That being said... Proceed at your own risk, and be careful and cautious... This is not book load data, it's computer simulation load data, and we know how computers are...

In 7mm rem mag with a 26 inch barrel, it gives a rough starting load of 50 grains IMR 4895(72% case fill and 99.8% powder burn, 42,000 psi ESTIMATE) has a velocity of about 2800 fps. A Max load would be 55 grains, about 80% case fill, 100% burn, and chamber pressure ESTIMATE of 54,000 psi(so still technically below max saami pressure, but getting close) has a velocity of about 3000 fps.



Sent from my SM-G996U using Tapatalk
 
45th edition Lyman load book (1970)
7mm Rem Mag

140gr bullet Sierra
start
IMR 4895 50.0gr vel 2744fps pressure 41.100 CUP

Max
IMR 4895 57.0gr vel 3054fps pressure 52,000 CUP

Cases Rem, primer Rem 9 1/2M

test firearm Universal receiver 26" barrel.

that's the closest I can get and the data is over 50 years old, so take it for reference ONLY not for use.
 
Yeah, that's a fast powder for the Rem Mag.
And i'd be worried about the low case volume on a start load.
Ideally you want to stay above 85%.
Too low case fill can give some wierd, bad pressure spikes.

If there's any way to buy, beg, borrow or steal a slower burning powder, jump on it!
 
std7mag said:
Yeah, that's a fast powder for the Rem Mag.
And i'd be worried about the low case volume on a start load.
Ideally you want to stay above 85%.
Too low case fill can give some wierd, bad pressure spikes.

If there's any way to buy, beg, borrow or steal a slower burning powder, jump on it!
Click to expand...
And yet there are people loading 223 with 45g bullets and 5.0g of unique and other reduced loads. Every time I think I understand the case fill thing, people start doing things that just don't make sense to me.

same as with my 38spl loads. cases 1/2 full of fast burning pistol powders that have significant gaps between powder and bullet, that have good velocity and consistent ES and SD.

https://thefiringline.com/forums/showthread.php?t=612848
 
Shadow9mm said:
And yet there are people loading 223 with 45g bullets and 5.0g of unique and other reduced loads. Every time I think I understand the case fill thing, people start doing things that just don't make sense to me.



same as with my 38spl loads. cases 1/2 full of fast burning pistol powders that have significant gaps between powder and bullet, that have good velocity and consistent ES and SD.



https://thefiringline.com/forums/showthread.php?t=612848
Click to expand...
I've put 8 grains of... Something under a 235 grain lead bullet in 45 colt. Had to point the gun up and bring it down slowly to make sure the powder got lit. Yeah, low case fill can cause issues, but I don't think 70% is anything to worry about.

Sent from my SM-G996U using Tapatalk
 
I agree with STD7MAG. I've loaded the 7 Rem for more than 40 years and have used nothing faster than IMR4350. The cartridge is at it's best at 80%+ case full. Using 50-60gr of powder in this case could cause some serious pressure variances. I would ask UNCLENIK on this one.
 
Older IMR data for the 7mm Magnum lists a maximum 52.0 grains IMR4895 behind a 150-grain bullet for 2880 fps and 51,500 cup - clearly they didn’t think it was a bad idea to use this powder with heavier bullets in the big 7…but then what do they know.

I’m not advocating its use, but if that’s what the OP has he could do worse.



.
 
the "% of case fill" isn't a uniform thing across all powders and cases.

Its related to the powder burn rate, but its not a direct linear thing. And rifle and pistol cartridges are each in their own world about this, too.

Its quite common to load pistol cases (and especially the larger ones originally made for black powder) about half full (or less) of smokeless and that's a full pressure load with certain powders.

4895 works quite well in slightly smaller to slightly larger than .30-06 volumes,

Even works tolerably well in the .375 H&H and the .458 Win Mag.

But when you get into the "big bottle" magnums its a little too fast for maximum performance and usually reaches the max allowed pressure peak at velocity about 100-150fps or so slower than can be achieved with a slower powder like IMR 4350. So, while it can be used, if you're looking to get the most speed from your magnum, its a suboptimal choice.
 
I completely agree with medium powders in large bores. The 2.5" mags are typically over bore, so that's why I advised caution.
 
Alpsman, pay attention to this post from 44 AMP:

"But when you get into the "big bottle" magnums its a little too fast for maximum performance and usually reaches the max allowed pressure peak at velocity about 100-150fps or so slower than can be achieved with a slower powder like IMR 4350. So, while it can be used, if you're looking to get the most speed from your magnum, its a suboptimal choice."

The take-away is larger calibers and heavier bullets perform better with "slower" powders. To recognize what's meant by "faster" and "slower" not difficult. "Faster" powders reach a peak pressure more quickly than "slower" powders. The net effect is the push on the bullet starts to decrease before it exits the barrel, reducing velocity. A "slower" powder peaks later but still is behind the bullet before it exits, so the velocity is increased.

When I started reloading in 1976, I used H4895 to push a 130gr bullet in my .270. I couldn't get the empty case out because the bolt locked up. The powder was too fast and as a result, the pressure was too high too fast. Now, understand, a reduced H4895 charge may have prevented that, but velocity would suffer. I read as much as I had time to do and started to use "slower" powders like H4831. Velocity increased and the lockup disappeared. Now, recognize as well, if you reach or exceed maximum charges of slower powders you will still get "lock-up" because the pressure tolerance of your rifle has been exceeded. That is an orange blaze, not a red, flag.
 
std7mag said:
Ideally you want to stay above 85%.
Click to expand...

That's the minimum case fill used by the old Powley slide rule. It's probably a good minimum for accuracy and ignition consistency. But for pressure spike problems from the primer igniting too big a powder surface area, Hodgdon tries to keep people to 70% fill or greater, and Dr. Lloyd Brownell's experiments with the 30-06 didn't reveal any pressure fluctuation issues until getting below about 55% loading density (see pages 53 and 54 (64 and 65 if you use the Acrobat page counter) of this paper). Also, he was loading IMR 3031 behind 180 and 220 grain Remington Core-Lokt bullets, which is a fast powder for 30-06 with heavy bullets today, and for which we would now choose something more like IMR 4350, but it still shows some faster powders can be used than you might expect.

The 50-grain Lyman load of IMR 4895 looks to be about 70% fill in 7mm Rem Mag. It will underperform by magnum standards, but will still be fine for deer. Expect that you'll lose 100 fps or maybe more if the powder is forward against the bullet when you shoot as compared to being back over the flash hole.
 
45th edition Lyman load book (1970)
7mm Rem Mag

140gr bullet Sierra
start
IMR 4895 50.0gr vel 2744fps pressure 41.100 CUP

Max
IMR 4895 57.0gr vel 3054fps pressure 52,000 CUP

Cases Rem, primer Rem 9 1/2M

test firearm Universal receiver 26" barrel.

that's the closest I can get and the data is over 50 years old, so take it for reference ONLY not for use.
Click to expand...

I realize the post says IMR 4895, not H4895. So the transition by Hogdon from surplus powder to newly manufactured probably does not apply.

But I will say I'd be very skeptical of 1970 vintage load data myself.

My example was PROBABLY H4895, But picture a group of Olde Retired Guys at the coffee shop, when they could still smoke a pipe with coffee after breakfast. One says "Hey,Dave,back when we were still elk hunting together
,you had a good 30-06 load you put together for that Mauser I built. That load always worked real good in that rifle. My Son is wanting to use that rifle to go hunting this year. Could you make some of those same loads for me?"

Well,Dave says "Sure"

Later,the Son brings the rifle and ammo to me. He says "I can't believe how this thing kicks!! I'm wondering,are the primers supposed to fall out like that? And that black stuff..."

Well,of course I look to the primers(that are gone) Gonna read me some of those "pressure signs" The primer pockets are splayed out. Scary stuff.

The powder was one of the 4895's. (Probably Hogdon. These guys hunted with the same Gunsmith Louie Baechler who used to sell me bulk surplus H-4831 for $1.60 a lb. )

I broke one down and weighed it. The charge matched up perfectly to a safe,under max load published in P.O.Ackley's "Handbook for Shooters"

I'm sure Old Dave conscientiously looked at notes and duplicated the exact load that shot safe and well in that rifle.

But,in good faith,he may have bought "Newly Manufactured" H-4895.

The red can DuPont IMR powders were still on the shelf in 1970.

I've loaded quite a bit of 7mm Rem Mag. Its a big case that has a relatively small bore. Consider its a necked down 458. IMR4895,if I'm not mistaken,is a good burn rate in a .458.

I'm not saying you can't use 4895. You can. Generally,if they bother to publish data,it will work. I would not push the upper limit. Settle for "Enough" Things can spike suddenly with big cases and quicker powders.
I never loaded 140 gr bullets. I generally used 160's. Some 150 Ballistic Tips. The 150's like IMR4350. I used H-4831 for the 160's H-1000 for 168's.

Reloader 19 and Reloader 22 work about equally well.
 
From the references I have on hand: 139gr in 7mm Rem Mag:

Lyman 50th Ed: bullet weights 120 to 175gr – no recommendation listed for H- or IMR 4895

Hodgdon #27: only lists loads for 120gr and 150gr with IMR 4895

Speer #12: IMR 4895 with 130gr: 46.0gr (2737fps) – 50.0gr (2964fps) – no pressures listed

Nosler #3: IMR4895: 140gr: 50.0gr (2920fps) – 54.0 (3130fps) – no pressures listed

Hornady Vol II (1973): only indicates “4895” 139gr 53.8gr (2900fps) – 58.0gr (3100fps) No pressures listed

Hornady “Vol I” 1991 (I can’t explain how II got to I eighteen years later): bullets 100gr to 175gr – no listing for either 4895
 
My Hornady Volume II is from 1973. I think later Vol. I and Vol. II labels were from when Hornady started splitting their data into two books, so you would have the same edition but with two volumes, which they have since ceased doing.
 
But I will say I'd be very skeptical of 1970 vintage load data myself.
Click to expand...

Of course, you should be. But then you should be skeptical of ALL load data. Its just prudent, we don't have the guns they tested the data in, and we rarely have the same lot#s of powder, primer and bullets. Which is why one always starts low and tests carefully until one knows just how the combination will act in our gun.

the OP asked for data, I gave what I had, and also gave the source, so what he does with it is his business.

I've always felt it was a poor idea to make something ALMOST the same as something else and give it almost the same name, where there is enough of a difference that confusing the two can create an undesirable (let alone unsafe) situation.

Cannister grade reloading powders are held to fairly tight standards lot# to lot#, if I remember right its something like 3% or less lot to lot variation. SO I trust my old data when used with my old components but with new stuff I TEST before I trust.
 
I had a Hodgdon book that said, at the time, they had gone to ±3% burn rate tolerance on all their powders but IMR, which were ±5%. But that was like twenty years ago, and I know they've kept improving their QC over time and overhauled it around 2000 in particular. But that begs the question as to what tolerances were maintained in the 1970s when they were still selling surplus powders. I've heard numbers as high as 10%, but don't take that as gospel. It is only a bit better than bulk grade. So it is much harder to know what the old load data was developed with.
 
You must log in or register to reply here.
Back
Top