Small Flash Holes on new Peterson 7mm-BR brass

M

mehavey

New member
Peterson recently began supplying new 7mmBR brass
(Thank-you. My 1988-vintage RP brass was getting a bit long in the tooth)

But they come with SMALL flash holes (0.060"±)
My old brass/old RCBS sizing dies are large (0.080") pin.

Before I grab a 5/64 drill and open the holes up to ~0.080", who makes small-pin 7mm BR dies (or a small-pin decapping/neck expander assembly) at this juncture?

(Nothing I see on the net for 7mm Br dies specifies which pin size)
 
you can get the small replacement pins for Redding dies and the Mighty Armory universal decapper or take a Lee or other brand decapping pin and chuck it in a drill and file/sand it down
 
mehavey said:
Peterson recently began supplying new 7mmBR brass

(Thank-you. My 1988-vintage RP brass was getting a bit long in the tooth)



But they come with SMALL flash holes (0.060"±)

My old brass/old RCBS sizing dies are large (0.080") pin.



Before I grab a 5/64 drill and open the holes up to ~0.080", who makes small-pin 7mm BR dies (or a small-pin decapping/neck expander assembly) at this juncture?



(Nothing I see on the net for 7mm Br dies specifies which pin size)
Click to expand...
Call RCBS and see if they can send you a new decap rod assembly with the X-small pin. Not sure if they were ever made with the X-small decap pin, but customer service might have some in stock.

I recently bent the decap rod in my 35 yr old 5.56 SB die and RCBS had me a new decap rod and extra pins within 3 days (at no charge)! Be aware that their newer rods use a decap pin with a head, unlike the old collet-style straight pins.

Sent from my moto z4 using Tapatalk
 
Unfortunately the "gripper" part of the RCBS de-capping assembly won't "grip" the small pins.
I could have gone with just a universal small pin rod (no neck expander) and used the M-Die I'm already using for Cast)

The New Redding, however, come w/ a small pin (`found that out).

I'll be interested to see the effect of small flash hole/smaller volume of Peterson cases using Cast bullets compared to the R-P case
7mm-BR-LEE-285-130-R-2-AA2495.jpg
s


Got the last one about an hour ago,
 
mehavey said:
Peterson recently began supplying new 7mmBR brass
(Thank-you. My 1988-vintage RP brass was getting a bit long in the tooth)
Click to expand...

And a big thank you to mehavey for this info since I share your circumstance.
My developed loads for the 7mmBR use IMR 4895. Do you think the smaller
flash hole will be a problem or should I go ahead and drill them out.
 
mehavey, I have some new Rem 7BR brass made for small rifle primer that was purchase in the early 80's and I also have few Rem 7BR nickel cases. I got pretty close to 1K cases and necked about half down for 22BR. I have factory 22BR FL sizer for small primer. I'd also build 7BR rifle and used some of the brass for that rifle.

I have about 150 new Rem 7BR brass cases. I've got Sierra new manual and looked at data for 7BR rifle and they list 7BR brass using 7 1/2 primer. One reason I used 7BR brass for 22BR was brass was supposed to last longer.

I got some 280 Peterson and fire form that for wildcat 280AI and it's pretty good brass.
 
When the 7BR was first introduced in the XP-100 (I had one) you could not buy cases, you had to make them from .308 Match cases with small rifle primer pockets. The small rifle primers gave less aggressive ignition which, it was believed, gave better accuracy. The less brissant primer and small flash hole certainly didn’t hurt accuracy in the small BR case, which was meant to mimic the similar PPC case with its small case volume and small primer pocket.


.
 
XP100-7mm-BR-AA28-130-B-Powder-Coat-WHITE.jpg

First shot at
- New Cases/new voluime
- BR4 vs #41 primers
- First powder-coat vs tried & true ALOX
- Powder Coated plain base previous not-so-so-good ALOX trial at this pressure

... and the list goes on.... :-)
 
Toaster Ovens are the new toilet paper of recent COVID shortage. So when I happened pn a (relatively) inexpensive Hamilton Beach EZ-Reach as the only thing left on a Wlamart shelf, I grabbed it.

First trial at controlling Temp to 400 degr (set at 360) resulted in this:

Bullet-Slump-Hamiltio-Beach-EZ-Reach-set-at-360.jpg


We're taliking 600dgr (+) for that to happen. Stuck a digital probe in this morning to find WILD fluctuations (hit 567 in 5 min when set at 360)

Word to the wise.....
 
Yeah. Domestic ovens often have poor coupling of the thermostat to the actual temperature inside. That delays the thermostat learning the truth about the temperature which allows it to overshoot the setting until temperature equilibrates everywhere inside. Everybody I know who has adapted a toaster oven to a process like this has gone on eBay and picked up a Chinese auto-tuning PID controller. With that, they set the toaster oven on maximum and let the PID controller take over. It has to tune once, where it runs the heat up and down to learn the characteristics of the oven. Once that is established, you are good to go. This one has the option to get it with a heat sink and 40A solid state relay for $22.45. You get to supply the power cord and toaster oven socket.

It seems like a lot to spend on a toaster oven, but once you have it you can control other things with it (when it isn't running the oven). Look in the cast bullets forum and over at the castboolits forum for more info.
 
Once I figured out just how badly it was overshooting because of P-Poor sensor placement, I figured how to handle it within the Powder-Coating cycle:

- Turn mechanical dial to 355/place digital cooking sensor in tray
- While heating, do the shake & (not-yet) bake thing with the bullets and powder.
- When sensor reaches 400 on its way to 580, unplug/open the door/let cool to 420, then plug it back in
- Heating cooling has equilibrated the volume and now the oven thermostat takes over to hold at a reasonable +/- 5 degr of 400

PITA, but it works now that I know what it was doing.

I don't know how ANYone cooks with this thing, however, with that much overshoot and that much off indicated temp even when it settles down
 
You must log in or register to reply here.
Back
Top