Forster NM 308 confusion

[TommyD11730]

Im confused, Forster states their NM die bumps the shoulder back 003. Dont I control the amount of bumpback by the depth of the die???
Im confused further by their diagram...
Having stuck my very first case in, you gussed it a 308NM die im not so sure Im going to use it. That is till someone helps explain this 003 bumpback.

 

[6.5SH]

It is intended for use with a rifle chambered on the minimum side of the SAAMI spec. The -.003 is the shoulder bump difference between it and their regular die setup to the same depth using the same shell holder.

If you poke around in this sub forum you will see other mentions of having dies or shell holders shortened to allow more sizing to occur when a particular combination wasn't enough. You can run into a hard mechanical stop and the die can't size things enough.

As to your need of this or not, you need to measure some brass fired out of your gun with a comparator then see if you can size it enough for your desired shoulder bump.

 

[FLIGHT762]

Yes, YOU adjust the amount of shoulder bump. The die is cut to give you .003" more, if you need it.

When you get a new sizing die, you clean the inside well to get the factory oil off then put a little sizing lube on a Q tip on the inside of the die. Use a good case lube first like Imperial to season the die. This helps not getting the first cases not stuck.

 

[TommyD11730]

Yes, YOU adjust the amount of shoulder bump. The die is cut to give you .003" more, if you need it.

When you get a new sizing die, you clean the inside well to get the factory oil off then put a little sizing lube on a Q tip on the inside of the die. Use a good case lube first like Imperial to season the die. This helps not getting the first cases not stuck.

In the past I had used the powder Forster suggested. Never had a problem... except the bench looked like I had a coke party.
The stuck case was on imperial.. litte bit on neck, qtip swipe inside the neck.
Lesson learned, stick with the powder on Forster.

 

[FLIGHT762]

From your description, you don't put case lube on the case body & down onto the case web?

 

[TommyD11730]

From your description, you don't put case lube on the case body & down onto the case web?

I used to spray the heck out of my brass. Lanolin.. One shot you name it. Now I use a qtip with a little imperial wax on the inside of the neck... lube the outside of the case with a little lube on my fingers.
Worked on my bushing dies.. not so much on my Forster.

 

[bluejay75]

Bore mop with imperial die wax massaged into it makes easy work lubing the inside of case necks. Once saturated I rarely have to add any to it. It makes any sizing operation much more pleasant. I swab all the necks then shake them in a bag. After that you can size and mandrel and not worry about friction.

 

[TommyD11730]

Bore mop with imperial die wax massaged into it makes easy work lubing the inside of case necks. Once saturated I rarely have to add any to it. It makes any sizing operation much more pleasant. I swab all the necks then shake them in a bag. After that you can size and mandrel and not worry about friction.

I like the idea of a bore mop. Much nicer then me and my qtips though.
Have to ask though... your useing it on a Forster sizeing (non bushing) die? Im asking as I thought Forster was anti lube other then the dry lube they sell.
Figured I would ask as the thread seems to be going that direction vs the bumpback.

 

[spife7980]

If you are full length sizing a bottle necked cartridge you need to use lube and an adequate amount of lube at that.

 

[bluejay75]

Forster FL sizer in both 308 and 6.5 Creedmoor. I didn’t get the NM because I didn’t understand it either. Even after reading this I don’t understand it.

I have maybe 4 other 308 size dies but the Forster is by far the best. Second would be the RCBS X Die.

 

[FLIGHT762]

I used a Forster 308 Win. National Match die for two decades. It just gives you the capacity for a little more F/L shoulder bump, if you need it. You set the die up just like you do with any other F/L die. It made accurate ammunition. I bought it for sizing my cases for use in my M-1A. No voodoo to understand.

I sold the set last year with a couple of extra 308 dies I accumulated over the years.