Shopmade Decapping Pin

[rhynardt]

Hi All

A friend of mine recently bent his decapping pin out of whack by not seating a casing properly . So he decided he could hammer the pin straight and then use it again. He forced it into a casing and it got stuck again , due to it not being straight at all. So now he was forcing it out again and stripped the threads off the neck sizer. Thats when he decided he might need help as the closest dealer that will have the pin for him is across the border and wants to charge him exorbiant money for a new one, about the same money as he paid for the whole die set. So he told me his story and i agreed to help him

I didnt take any pictures of the process of making the pin but i got the finished pics


As you can see the top one is a bit worse for wear and has a fer threads short

Here is the finished assembly





Made the pin out of an old air cooled deuts tractor engine's valve pushrod. Very hard stuff, carbide only

 

[brino]

Hey rhynardt,

I have also been know as "a few threads short", but could you please educate me on what this "decapping pin" is used for?

Thanks,
-brino

 

[TOOLMASTER]

TO REMOVE THE PRIMER FROM A AMMO CARTRIDGE SO A NEW PRIMER CAN BE PUT IN

 

[rhynardt]

Thanks Toolmaster, thats exactly its purpose

 

[Tozguy]

The part that rhynardt made is actually a stem for a reloading die. This particular die is designed to resize a fired case that has expanded slightly as a result of the high chamber pressure it had to hold. The stem serves two purposes. When the fired case is pressed up into the die, the small pin on the end of the stem goes through a flash hole to punch out the used primer (mentioned above). On the same stroke the die is squeezing the neck and/or body of the case back to smaller dimensions. When the stroke is reversed and the case is pulled back out, the bulge on the stem next to the pin expands the neck out to a uniform diameter.

That's an excellent job you did, the stem is probably better than the original. Did you reuse the original pin?

 

[rhynardt]

Tozguy, thanks for the proper explanation. I reused the front expansion tip and pin if that is what you mean. I think the stem as you say is a bit stronger than the original. Hopefulle my friend wont be able to bend/destroy this one. If he does i think he should take up another pastime

 

[Big Bore Builder]

I make dies for the wild creations I sometimes chamber in a rifle. I start with a both a resize and a finish reamer. Over the years I have learned to make the decapping rod as large a diameter as possible and use a quality material. Some photos below.

Note the resize die has a removable neck sizing bushing, to be able to change out the bushing for different inside diameters.






The small cartridge in the below photo is a 308 Win.

 

[wrmiller]

Now I know where I can get custom dies...

Do you make the sizing dies out of anything special?

 

[rhynardt]

Big Bore Builder. Thats some fine dies you have there! What materials do you use for your dies and decapping rods/stems? I used an old diesel engines valve pushrod to make the decapping rod/stems. Dont know anything about the steel except that its very hard, hss didnt touch it


Sent from my GT-P5100 using Tapatalk

 

[Big Bore Builder]

The 50 BMG dies are 4140, not heat treated, as the cases are fire formed to the chamber and all I need to do is size the necks, hence the interchangeable neck size bushings.

Other dies are made from 1 " diameter conveyor chain pins (Think big drag chains used in saw mills and power plants). It hardens to a very nice case. I have a milk crate of pieces 6 to 10 inches long, real handy if a tough steel is needed. 4820 alloy.