7mm-08, H1000, 139 or 140 grain

Cleftwynd

Cleftwynd

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I have no data for such a load anywhere, but would like to attempt a reduced load with a 139 or 140 grain bullet and H1000 in the little 7mm-08. I have a few components I would like to use up.

Does anyone have any suggestions?

I was thinking of starting at around 40 grains.
 
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The way I see it, powder burn rate is a function of relative case capacity, barrel length, and bullet weight. Depending on how long the barrel is, I'd have to agree that H1000 is slow, but if you've got it may as well use it.


Using Hodgdon's reloading data center, I see that IMR 7828 is close to H1000 and with a 168gn projectile it recommends 46-49 grains. Using the lighter projectile should reduce max pressure so why not start there?
 
Cleftwynd said:
I have no data for such a load anywhere, but would like to attempt a reduced load with a 139 or 140 grain bullet and H1000 in the little 7mm-08. I have a few components I would like to use up.

Does anyone have any suggestions?

I was thinking of starting at around 50 grains.
Click to expand...


I'm not sure you can get much more powder in the case than that???? Don't have any info. for the 7-08 with H1000 but I did load up some 140 berger vld hunting bullets with 45gr. of IMR-4350 a few days ago and shot my best ever 3 shot 100 yard group, measured .140 ..... mostly likely a fluke but still felt good at the time.
 
Typo, I meant 40 grains, will fix asap...lol

Actually it looks like a full case, 100%, woulld be way under pressure anyway. I am going to give this a shot! Will report back once I try them @ 100 and 200 yards.
 
I did exactly the same thing you are wanting to do. Model 7 in 7mm-08.

I wanted a round to use from a tree stand, that would be viable out of an already proven rifle I had on hand, that wouldn't have high velocity for the close ranges I would be shooting at. no more than 100 yards.

I tried several extremely slow burning powders and settled on H1000 with CCI250 primers.

At first, with loads that only filled the case about 3/4 full, accuracy was terrible.

I kept filling the case until it was full to the base of the neck. Accuracy was very good and consistent.

The problem wasn't to much velocity but that it was a compressed load, which some like when using relatively slow powders.

I then dropped the charge back, until it just reached the angle on the shoulder. The long 140 grain bullets took up enough space when seated to just fill the case so there weren't any air pockets.

This worked exactly as planned. Lower muzzle flash, lower consistent velocities and very clean burns.

Caveat, the accuracy falls off with standard CCI200 primers.

Caveat, this is still a potent enough combination to drive a 140 grain bullet through a bear or deer out past 150 meters.

Recoil is very tame.
 
I have some loaded with 46 grains of H1000, was right at neck, full but not compressed with a 140 grain boatail CAOL 2.800. Can't seat any longer as that is less than 10 thou off the lands, and close to max for the magazine in the Model 7.

Will see how they feel and group tomorrow.
 
You can use full cases of H1000 in the 7mm-08 with even the 175 gr bullet, and the pressure remains modest. I've done the same in the 6.5X55 with the 140gr, and found both loads to be quite accurate, but short on max MV (slightly faster powders like H4831 beat it and are accurate), which would only matter at extreme range, e.g. 500 yds +.

P.S. Barrel length has no bearing on powder selection.
 
I would just step back some W760 or H4350 , you'll find some 2500 or 2600 ft/sec loads and be able to find an accuracy node in there somewhere.

When I am home I will check my spreadsheets for you.
 
I just want to burn off this H1000 that is kicking around, only enough for about 90 loads at 50 grains anyway. I am now up to 48 grains, slightly compressed, at 47 grouping was much better than 46 and 46.5. 47 and 47.5 were grouping about an inch at 100, will try the 48's and see what happens. Very mild report and kick too!
 
Well what I found was a node for 140 grain Accubonds with W760 right at my start charges, I would imagine if you went a grain or two below the published data you could still stay in that node and have a very subtle load with accuracy, this doesn't however help ya out with the H1000 which I don't believe would give you practical and possibly unsafe results.Personally I wouldn't use the H1000 , save it for a larger cased chambering.

I have had good results using the Hodgdon load center for starting points.
 
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