Gunsmithing Forster 308 National match Die

[waste_knot]

My Redding bushing die will not FLS fired Lake city brass to fit my chamber. New Lapua and Win fit fine.
A RCBS FL die will resize the brass but it makes the necks about .329 or .301 ID which is way too small.
Does anyone know what the national match die from Foster dimensions are.

 

[turbo54]

Re: Forster 308 National match Die

I have the Forster 308 NM FLS die.

Removing the expander ball, and sizing a piece of LC72 Match brass, the neck OD measures .325"

The expander ball itself mics .3073".

Hope that helps.

 

[waste_knot]

Re: Forster 308 National match Die

Thanks for the reply. That is some of the stuf I'm trying to find out. It's seems that most of the stock dies size the neck down about 0.010 below and then let the x ball size it back back for neck tension. I found the Forster catalog that states the NM die pushes the headspace back .002 as well. I need the base sized down as well for this tight chamber.

 

[turbo54]

Re: Forster 308 National match Die

I recently built a 284Win, and it has a pretty tight chamber. I've bought a number of different batches of once-fired brass and my Forster FLS die won't get them to fit. So I bought a Redding SB FLS die, and it's good to go.

Personally, I'm not sure why you're fretting about the neck getting sized .010" undersize during the FLS process, but it sounds like what you want is a SB bushing die. Not sure I've ever heard of one.

Another option is to send your RCBS FLS to RCBS, and have them hone the neck portion of it out to meet whatever spec you like.

Once you FLS/SB size the once-fired brass to fit your chamber, your bushing die oughtta do everything you need it to do.

 

[9H_Cracka]

Re: Forster 308 National match Die

The Forster NM die is designed to allow you to push the shoulder back so headspace is at minimum SAAMI.

If you want control over the neck, go to a bushing die, plain and simple, and decide if you want the last thing to touch the neck (therefore set the ID or OD) on the inside or outside.

** hint ** - unless you have uniform neck thickness, the only way to deliver consistent neck tension from the bullet's perspective is by touching the INSIDE last, not the outside.

 

[turbo54]

Re: Forster 308 National match Die

Agreed. The NM die is really intended for autoloaders.

A SB die is intended to resize brass fired in a SAAMI (or bigger) chamber back to minimum SAAMI specs, such as those in tight "match" type chambers.

Once you've SB FLS'd, you'll only need to use your bushing die in the future, provided you only fire the brass in your tight chamber.

I recommend ditching the expander ball, and performing the final neck sizing with a Sinclair expander die fitted with a neck turning mandrel for .002" neck tension.

 

[9H_Cracka]

Re: Forster 308 National match Die

I recently went to a small base Redding S FL sizer in 308 after finding out the reamer that did my previous Palma barrel was a tad over spec in the rear of the body of the case. Had to do so to re-use my old brass.

Using Lapua brass, which has good uniform necks, I am using the decapper pin holder only, no expander, that came with the die, and the appropriate ti nitride bushing.

This lets me size the case in one step.

 

[asbestosglove]

Re: Forster 308 National match Die

Redding makes a small base bushing die. AG

 

[Hookman]

Re: Forster 308 National match Die

I bought the Forster NM 308 die for my M1A. I asked Forster the same question and here are the dimensions they sent me:

"The inside neck diameter of the 308 NM die is .328” and the expander .307”

I use LC Match 93 brass and with those dimensions, I believe it works the brass too much. Option 1, send the die back to Forster to hone the inside neck diameter. They will open it up .008 max. so that will give me .336. this will work fine for Win/Fed brass but for LC brass a .338 is what I'd like to have. Option 2, buy a Redding Small base body die and a Forster Bump Bushing die with a .338 bushing. The second option is what I went with. It gave me more flaxibility and works well for my reloading setup.

You may be able to just buy the Redding Small base body die and be done with it.