Reply with quote #1
I need fire forming loads for the 6BRX. If Bob Crone could give his load for his fire forming proceedure, that would be great.
Reply with quote #2
While I don't have any FF loads I was planning on using standard 6BR loads. I do have a reamer on order as well as a 22BRX reamer for my BAT action.
Reply with quote #3
To save wear on his barrels, Bob Crone tells us he likes to do his fire-forming during local matches. He uses 29-30gr Varget with a 107gr Sierra normally. He does neck-turn his cases, and he may now be using the Shehane method of turning the cases part-way to create a false shoulder--but we're not sure about that. He used to just long-seat/hard jam the bullets to give firm headspacing, then shoot.
Reply with quote #4
I form Dashers and want to add you should use CCI or other hard primers. I get a lot of pressure while forming using just 27.0 of N150 and 105gr or even 88gr bullets jammed into the lands.
Winchester SR primers come out with huge craters or pierced, even at these mild loads, while the CCI BR4/450 shows no problems.
Reply with quote #5
I have fire formed a box of Lapua 6br brass in a Barnard action prone rifle chambered for 6BRX. I started with 29.5 gr of varget with Rem 7.5 primers and Sierra 107s. I initially got pierced primers at this low pressure. The new shoulder was rounded and not well defined. Moving up to 30.5 gr of varget stopped the piercing and gave well defined shoulders. I think what is happening at the low pressures is the following. The primer is moving rearward faster than the shoulder is moving forward. Thus,the primer cup is left unsupported for a very brief moment, allowing the primer cup to rupture around the firing pin.
Reply with quote #6
I get nice cases, no rounding etc. I didn't have this problem with the CCI before, and has some Winchesters laying around. The load seems to shoot really nice (<0.25" while forming!!!). I'll try upping the load with the Winchesters to see if I can repeat what you found. might be an interesting thing to know.
Reply with quote #7
Scott, I have fire formed a hell of a lot of cases for myself and advised many other guys on the procedure with no problems because I made all the mistakes long ago!!
1. If the case is a blow forward type modification (with shoulder,LOL) "Always" use a false shoulder.
2. Regardless if you are just changing the shoulder angle or doing the "Blow Forward as above", "ALWAYS" use a bullet long enough to have good support in "most" of the neck and "Firmly" engaging the lands, this is very important to form the case properly/correctly.
3. Finally you will hear different versions of what kind of powder charge to use, trust me, this is important! Use a good "stiff" load of medium burning powder that is recommended for the case you are using.
If you follow these instructions you will loose very few if any cases and they will be fire formed without "Bouncing" the case and/or stretching the brass in the web area. No Fuss no Muss!
Reply with quote #8
I agree--false shoulder is definately the way to go!