300 Wby Mag crushed shoulder

[Early Cuyler]

I'm trying to reload some 300Wby Mag to do a ladder test and when seating the bullet, the case is getting crushed. When trying to seat the bullet the case neck telescopes into the shoulder considerably. It should be noted, the bullet does NOT seat into the case at all. Upon removal, I can pull the bullet out with my bare hands. And I'm no Lou Ferigno.

I've cleaned the dies and checked the length of the cases. They're not the issue. I checked the bushing on the resizing die and it is measuring .3055". The bullets I'm wanting to use are Hornady Interlocks (my dad wants to use it hunting elk) measuring .308" dead nuts on. I do not have a proper caliper to measure neck tension.

These bullets have a flat tail rather than a boat tail and I'm wondering if that is the issue. I've also put a chamfer on the inside of the case along with lubing the bullet with no improvement.

My next guess is to either get a wider bushing to open up the case necks more, or try different bullets.

What say you, Hide Gurus? Give me your guidance and wisdom.

 

[DJD3]

Re: 300 Wby Mag crushed shoulder

I bought a brand spankin new set of dies about 10 years ago, that had a spur on the inside. was doing same thing. Crushing the case. I don't know if this is the problem with yours, but worth checking. Also, if you can pull the bullets by hand, would not a wider bushing decrease neck tension?

 

[Early Cuyler]

Re: 300 Wby Mag crushed shoulder

Well I can pull the bullets by hand because they don't go into the neck except a couple of mils. A wider bushing would reduce neck tension but I also just tried to load a SMK HPBT and it crushed the shoulder again.

 

[buffybuster]

Re: 300 Wby Mag crushed shoulder

Try some boatails first, to see if those seat properly. If they do, might be an alignment issue with the flatbase bullets. Also make sure you have the die backed off enough there is no crimp being applied.

 

[MitchAlsup]

Re: 300 Wby Mag crushed shoulder

Just to be sure::
its the inside of the case neck that measures 0.3055?
and
the chamfer you put in the case neck is at least 1/3rd of the wall thickness?
and
you measured the case neck and the bullet diameters with the same measurement tool?

 

[DBohn]

Re: 300 Wby Mag crushed shoulder

If your neck sizing bushing actually is .3055" you need a bigger bushing. Take the thickness of the brass at the neck, you might want to do it in several different spots and on several different cases and take the average, double that and add .308 and subtract +/-.002 depending on how much tension you want.

 

[Early Cuyler]

Re: 300 Wby Mag crushed shoulder

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">Just to be sure::
its the inside of the case neck that measures 0.3055?
and
the chamfer you put in the case neck is at least 1/3rd of the wall thickness?
and
you measured the case neck and the bullet diameters with the same measurement tool? </div></div>

The outside diameter of the bushing is .3055". And yes, I used the same calipers for both measurements.

I tried seating a boat tail bullet to no avail. Even with a proper chamfer it didn't work. I guess I'm gonna look for a new bushing.

 

[MitchAlsup]

Re: 300 Wby Mag crushed shoulder

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: halcyon575</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">Just to be sure::
its the inside of the case neck that measures 0.3055?
and
the chamfer you put in the case neck is at least 1/3rd of the wall thickness?
and
you measured the case neck and the bullet diameters with the same measurement tool? </div></div>

The outside diameter of the bushing is .3055". And yes, I used the same calipers for both measurements. </div></div>

What is the inside neck measurement?

 

[DBohn]

Re: 300 Wby Mag crushed shoulder

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: halcyon575</div><div class="ubbcode-body">
The outside diameter of the bushing is .3055". And yes, I used the same calipers for both measurements.
</div></div>

The outside diameter of the bushing means nothing as they will all be the same depending on what brand you're using. The size of the bushing refers to the ID which is what size it makes the OD of your neck after sizing. Your bushing size has to be bigger than .308". For example with my .338 Lapua I run a .360" bushing on Lapua brass.

 

[former naval person]

Re: 300 Wby Mag crushed shoulder

Look at Buffybuster's post...you may be trying to seat a bullet in a die that is screwed in too far and the mouth of the case is being set back, collapsing the neck. Try unscrewing the seating die from the press about one turn, and then set the OAL with the bullet seating punch.

 

[FLIGHT762]

Re: 300 Wby Mag crushed shoulder

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: former naval person</div><div class="ubbcode-body">Look at Buffybuster's post...you may be trying to seat a bullet in a die that is screwed in too far and the mouth of the case is being set back, collapsing the neck. Try unscrewing the seating die from the press about one turn, and then set the OAL with the bullet seating punch. </div></div>

This ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ could very well be the issue. Seater die not backed off from the shell holder and slightly crimping the case mouth.

 

[c ward]

Re: 300 Wby Mag crushed shoulder

If your trying to use a bushing with .305 id your necks are way too small . You need to take bullet dia plus neck thickness x 2 minus your desired neck tension to get the starting bushing and adjust from there .

So it looks something like this , .308 plus .014 x 2 minus .003 for .333 starting bushing size . You have to adjust usually bigger after actually sizing some cases . A .305 bushing will give you a neck id around .277 which is not going to work .

 

[c ward]

Re: 300 Wby Mag crushed shoulder

Reading your post again are you measuring the id of the neck bushing or the od of the expander ball / mandrel ? What is the id measurement of the necks of the sized cases ?

 

[DBohn]

Re: 300 Wby Mag crushed shoulder

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C Ward</div><div class="ubbcode-body">Reading your post again are you measuring the id of the neck bushing or the od of the expander ball / mandrel ? What is the id measurement of the necks of the sized cases ? </div></div>

OP, if this ^ is what you're doing and referring to the expander ball as the bushing then Buffybuster probably nailed it and you have your die screwed in to far. We need some more information to help you.

 

[Early Cuyler]

Re: 300 Wby Mag crushed shoulder

Well once again, I see why being a member of this site is humbling. As it turns out, the die was in too far.

I was thinking that when I was using the plunger that the resistance I was feeling (after initial adjustment) was the bullet. However I can tell it was now still the neck and I needed to back it out even further. I'm using an RCBS ammomaster press and it threw me off. I had the same problem before with reloading 50BMG brass and didn't need to back it off near as much as with the 300wby mag.

Oh well, as always THANK YOU for your help and patience in my limited reloading vocabulary (a long time ago in a galaxy far far away SOMEone told me the "mandrel" was called a "bushing" and it stuck).

 

[Coletta]

Re: 300 Wby Mag crushed shoulder

I have done this before with rcbs dies. Wish I could have helped you