Hotburn76

I have a 204 that I am getting ready to work up some loads for. I heard on another forum that my brand of rifle has been know for having really long throats in them. I still need to do a cast of mine to get the exact measurements, but used a depth mic and came up with a rough measurement of 1.883 the spec for my cases is trim of 1.84 and a max of 1.85 When I do a cast and come up with the actual number and say it is close to 1.883 +- is it better to let my cases get longer and fill up some of the throat rather then my cases being so short? Does having a long throat and trimming to case specs like having a normal throat and under trimming your brass? Would it be the same affect? Any advice would be great from people that have encountered this.

HEAD0001

I have about a 50% success rate with those type chamber's. I have been able to get 50% to shoot well, and the other half never did pan out. IMO if you have a long throat or a lot of free bore then barrel alignment becomes the main concern. If the chamber and barrel is in perfect alignment then bullet jump is no problem. If you have an alignment problem then get rid of the rifle.

You also have to make sure you do not have any bullet runout with the longer chamber. IMO a longer chamber is just a bad thing. I normally just get rid of the firearm and start over. I have ran into a few of these in 223 Remington's,308 Winchester's, 30-06's, and then obviously some magnum's.

I once had a 7mm Weatherby Magnum that I wanted to wrap around a tree. But I finally did get the rifle to shoot. But it took a full year to get it right. Tom.

Hotburn76

Currently my best group to date is .75 at 100 yards with 4895 and 39 grain BK. I found this and thought it may be something I can do to improve my group a little more. I think the gun is ok and has potential, just am new to all this and learning more and more.

So would your advice then be to let the cases grow and fill the throat some more?

HEAD0001

There is no need for a longer neck as long as you have adequate neck tension on the bullet you are using. All a longer neck is going to do is cause problems with your brass. The longer the neck, the more the brass flow. The more the brass flow the larger the chance of a variable brass thickness. I would trim to standard trim length.

A tight neck is normally a measurement of neck diameter, not neck length. Just make sure you have consistent neck thickness(why reloader's turn their neck's), neck tension and bullet run out. That is all you can do. If the chamber and barrel is straight then these steps will be adequate. If the chamber and barrel is not straight then it will not matter what you do.

This is just my opinion. Tom.

gunnermhr

Correct me if I'm wrong. I'm not familiar with the 204 but measuments are measurments. The Throat refers to where the bullet sits before it gets into the rifling. Not where it necks down from where the case ends and the bullet begins. If your talking about where the case ends Never ever let the case get long enough to where the neck of the case is getting into the Throat where the bullet is. THis will not allow for the case to expand and release the bullet properly and you will have excessive presure, Dangerous pressure. If you are actually talking about the free bore you don't need to do a casting, simply buy a Stoney Point bullet comparitor and all your questions will be answered. I guess Hornady bought Stoney Point. You can tell exactly where the bullet and the rifling are in comparision to each other. Once you know that number you can get started. Some bullets like to have some "jump" before the rifling and others like to be "jammed' into the lands. Figure what bullet and powder work best and then start playing with the seating depth.

Okiegunnut

If you load the bullet to the lands back off your powder because your pressure will increase a great deal. You can use less powder and get same velocity. My 2 cents

falcon

With a bolt action rifle there is a much easier method of determining proper OAL for that gun. Take a case with a resized neckand seat a bullet very long. It is a good idea to put some grease on the bullet sothe dummy round comes out of the chamber without sticking. Stick the dummy round in the rifle and close the bolt.Eject the round andmeasure the OAl.Seat the bullet in your loadso that the OAL is .010-.040 shorter than the dummy round.With a long throat the bullet is sticking way out of the case, not to worry.

Several of my rifles have long throats and they shoot just as well as any other rifles providing the re-loaded round is straight. In using the above method make sure that bullet runout is at the absolute minimum.

Pawildman

This procedure works fine, but also keep in mind that if you are working up a load for a box magazine hunting rifle, the loaded ammo can't be any longer than what will load into the magazine or you'll be out in the woods with a single-shot rifle the first day of hunting season. Your cartridge total OAL cannot be greater than the length of your magazine. Some of us dummies learned this the hard way......................

falcon

"Your cartridge total OAL cannot be greater than the length of your magazine."

I had that in my post and took it out before it was sent. Oh well.

Okiegunnut

Your oal can be longer than your magazine but as you said you end up with a single shot rifle.