Is 39.5 grains of IMR 4350 too hot for Hornady 60gr SP bullets? They are used in a new Mod. 70 Stealth, 22-250.

I could not find any data on this particular bullet for 4350, but Ken Waters "Pet Loads" shows 39 gr as max for 63gr bullets.

So, I felt 39.5gr 4350 would be max. Of course, this turned out to be my favourite load (just under 1/2" group with 4 shots).

There are no physical signs of excessive pressure, caliper measurements of cases show no expansion of the case at the web, primers look fine, no resistance on opening the bolt. Measurements behind the shoulder are .010" larger on fired cases than on full resized cases, but this is consistent across all loads and should just be sized for the chamber.

It just seems a little LOUDER than the other loads, but I don't have anything to compare to now. I just need to know if I should pull apart the 40 others I loaded.

I don't plan on using these loads for long, and will develop for 50 or 55 grain bullets, but 200 of these were given to me....

Just because a load is max in one rifle doesn't necessarily mean it will be max in another. For that matter pressure can vary considerably by changing from one lot to another of the same powder.

It sounds to me as if you have made the necessary checks for excessive pressure and have a good, safe load for your rifle. I'd shoot them up and have some fun but probably check a few more for any pressure signs.

By the way: How's the rock chuck shooting these days? I lived in Twin 25 years ago.

I half of gr of powder for 3 grs of bullet should be just about right. If you have easy bolt lift primers look ok vel. is about where it should be I don't think that it well cause you trouble if any of the three shows signs then I would back it down. .5 in groups well kill thing a long ways out there.

In what I have seen in Kens loads they run a little on the hot size. It sounds like you have a good load. Watch if you load and shoot in cool weather. pressures will go up with the temp. If you change any of the components there could be a problem always reduce the load and work it back up.My 22/250
shoots hi pressure loads under 1/2" mol but all I am doing is shortining the life of the barrel.
hivelosity

Thanks for the info- what a great board.

Rock chuck shooting has been great this year, I'm just really getting into shooting and reloading, hence my concern over this load.

Some 200 yard 'chucks are just waiting to field test this load today....

Rockchucker:

It would appear that you have done your homework in developing this 22-250 Remington load and it would seem you have no pressure problems with it. However, I can understand being a little nervous without published data to work with.

I pulled out some of my old reloading manuals and found some stuff that may be of some help to you.

The 2nd and 3rd Edition of the Sierra Manual list 40 grains of IMR 4350 as maximum with a 60 grain HP, with a published velocity of 3500 fps. (26 inch barrel)

The Hornady Volume II lists 40.5 grains of IMR 4350 as maximum with a 60 grain Spire Point, with a velocity of 3600 fps. (28 inch barrel)

The Nosler Number Three manual lists 39 grains of IMR 4350 behind a 60 grain Solid Base bullet (now discontinued) for a velocity of 3670 fps as maximum. (24 inch barrel)

I hope this is of some value to you.

R Flowers

Are these charges individualy weighed or from a measure?

All loads have been individually measured.

I shot ~20 of these loads at chucks last night (got 2 at 300+yds!) and still have no signs of excessive pressure.

I am being very carefull to not let the cases be exposed to heat/sunlight while shooting. So far so good?

quote:

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Originally posted by 1894:
Are these charges individualy weighed or from a measure?

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Rockchucker,
What barrel twist are you using? Question is because I have a standard 1-14" twist and I have heard that you cannot use the 60 grainers in it. (Accuracy reasons). I would love to be able to use them.

As for your load, it does sound safe. Sounds like you have made all the needed safety checks.

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Safety & Ethics,Accuracy, Velocity, Energy
Joe M

JoeM

I am also shooting a 1 in 14" twist barrel, in a 26" length.

As for accuracy, the few chucks I haven't hit have been due to operator error, not the bullets.

Out of 10 loads tested, I had 5 groups of 4 within 1" with the 60gr bullets. The rest were out to 3" but nothing wild.

I have an old Hornady manual (copyright 1967)that lists a 60gr bullet and 4350 at a max load of 40.5 grs.......3600fps