Major problem loading .375H&H

[njc110381]

I've just crawled out of my reloading den cursing my luck. I'm really confused! Here's my problem.

 

I've just upped the load from start load to 2grns more. Not a big step in H&H terms. To be on the safe side I thought I'd load to min OAL for the max load, even though I'm well under. I had some trouble with the last lot so (Don't grill me for this too much) I pointed the rifle out of the window and checked the round would chamber. It was a tight fit! Turns out the rifle is seating the bullets to 3.540, but the min OAL for max load is 3.600. What's the deal here then? Surely the min OAL should chamber???

[Alycidon]

Check case length and loaded neck diameter first. The end of the case neck might be fouling.

 

A

[njc110381]

They're new cases, full length sized and loaded. It's actually seating the bullets deeper into the case if I ram the bolt forward on them. Wouldn't that mean the cases are going in ok but the bullet is seated past the lands at 3.600?

[PeteL]

Njc,

Have you checked your actual max loaded cartridge length by inserting a bullet in the chamber and measuring as in the procedure at the end of the following article?:

http://centrefireuk.com/viewtopic.php?f=3&t=1007

You may find that the max length is not what you think it is or should be. As I'm no gunsmith, I don't know what you can do about it, other than take it back to the Dealer.

 

I doubt that the following is your problem: Many years ago I bought a 375 from Heym (SR20) on a special order(I'm left handed). Having determined the max loaded cartridge length, as above, I found that the dummy round I made up would not go fully into the chamber, although one made to SAAMI spec would. Bore sighting was difficult also. I eventually found that the action and the barrel were not in line.(There were other things wrong, as well) It went back to the Dealer, a bit sharpish.

Peter

[Alycidon]

It sounds like the chamber is too short, you need to take it up with the dealer IMHO. Pushing the bullet back into the case is a sure sign that the bullet is in the rifling hard.

 

A

[njc110381]

It's an old gun, I doubt much could be done about it now. It shot fine with Remington factory ammo in Canada, in fact it shot very well. Is there a chance that the bullets I'm using can't push up the barrel as far as most because they have a very blunt nose? A more rounded bullet would be narrower at the point and would fit?

 

I can't see as there's much I can do about it apart from buy more pointy bullets!

 

I couldn't read the link, it needs a password to get in. Thanks for trying though

[Alycidon]

In that case can you get some Remmy ammo here to try then as you say build a round to emulate it. You may be able to find out whose teh factory remmy bullet is, its likely to be one of the US makers I would think.

 

If they are still in busines what do the guns builders say about the issue ?.

 

A

[njc110381]

It's a BRNO 602. Not run the problem past them to be honest. I figured as it's worked fine up until now there's no point moaning. I was just a little shocked that a round built to spec wouldn't chamber!

[Alycidon]

Maybe it was chambered for light bullets and Russian rabbits . Always thought the 375 was a good rabbit spreader !!

 

A

[Guest Coltauto]

I've just crawled out of my reloading den cursing my luck. I'm really confused! Here's my problem.

 

I've just upped the load from start load to 2grns more. Not a big step in H&H terms. To be on the safe side I thought I'd load to min OAL for the max load, even though I'm well under. I had some trouble with the last lot so (Don't grill me for this too much) I pointed the rifle out of the window and checked the round would chamber. It was a tight fit! Turns out the rifle is seating the bullets to 3.540, but the min OAL for max load is 3.600. What's the deal here then? Surely the min OAL should chamber???

 

3.600" is the maximum COL but the maximum length when used with a particular bullet may be less depending on the bullets ogive, or sharpness of the slope that forms the bullet's tip. One of the reasons for loading with a bullet comparitor is to identify where on the length of the bullet it's diameter exceeds rifling (bore) diameter. That said, 3.540" is short for almost any bullet. Did you die coat the bullet and check where contact is being made, or mic the neck after crimping to see if it is being forced oversized and binding in the chamber? Curious what bullet type you are experiencing a probem with and what powder charge.

[casts_by_fly]

I know you're talking about getting rid of that gun, so how much work you put in will depend on your intentions.

 

However, since you already have the gun that is where you have to go from.

 

Make a dummy round for your gun. Start with an empty casing, deprimed and FL sized. Chamber it to make sure it chambers. Then seat a bullet to what you expect the OAL to be. Measure the outside neck diameter and compare with the Rem rounds. Assumming everything is good to there, chamber the round. If it is too long, the bolt won't close. Pull it back out, set the deating depth 5 thou deeper and repeat. Continue until you have a round that just chambers with a tight bolt. That is going to be your length for a jam fit and your max length. From there back it off until you get to the length you want to reload at. Pretty simple and easy to do quickly. Just remember, no primer and no powder.

 

Thanks

Rick

[Andrew]

Try this: Take a cleaning rod and run it to the bolt face with the bolt closed on an empty chamber. Carefully mark the rod at the muzzle with a sharp pencil. Pull the bolt and set it aside. Drop a bullet ("head" for you) nose first into the chamber. Press it into the rifling with another short rod. Run the cleaning rod back into the muzzle until it touches the bullet nose. Mark the rod at that point, at the muzzle. Pull the cleaning rod and measure the distance between the marks with a caliper. That's the max OAL... or roughly so. ~Andrew

[Guest Coltauto]

Or you could buy an inexpensive COL gauge and test case that would allow you to check proper COL with any bullet you load. I think just the fact you can seat a bullet deeper by closing the bolt of your rifle tells you the ammo is assembled improperly, especially for a heavy round like the .375 H&H. Also, every reloading manual provides the proper outside neck diameter reference. And of cours each bullet has a COL limit based on ogive interference with rifling or adequate seating depth. Then the comment about adding 2 grains as not signficant in a big case where you are varying seating depth by 0.060". Depending on the powder type, those two changes could increase pressure by 12,000 PSI.

 

I'm not from the U.K. so maybe this thread is tongue and cheek and you guys are joking?