SAC does not currently offer 300NM, nor does Area419. Both of them are supposed to size the base smaller than regular dies. I am using a recent-production Redding S-Type and I'm having a terrible time with clickers on the 3rd firing because it isn't sizing the base enough. I've found only two other options that might solve the problem - 1) Cortina Mandrel Expander die that also resizes the base smaller than a normal sizing die, and 2) Micron Precision bushing die that sizes the whole case, including the base to a smaller dimension than regular dies. The Micron was out of stock and was expected to be a month out so I ordered the Cortina Mandrel die on Friday, primarily just to resize the base. Then I checked today and the Micron was back in stock so I sucked it up and ordered it too. Hopefully, one of them will stop the clickers. Interesting to note is that I've been using the Redding Type-S in 338NM (same case except for the neck) with no problems since 2014. I have to wonder if my 300NM Redding die (recent production) is out-of-spec.
I did OK until my 3rd firing. Keep us posted. Mine might be out-of-spec?
Some great info thanks for sharing. What size bushing are you using? 335?
I’m using Lapua brass and Berger 245’s.
I bought the jgs 35 norma imp aw reamer and a micron die to match. Had to send it back as it was overworking the body by about 6 thou iirm.
Nice die but it wasn't the best cs. I did eventually receive a working die. 8 sizes in and no clickers but I do get the weird line above the web like most folks at matches I see running 300nm imp chambers.
I top out at 3060 with 87 gr of retumbo and the newer 230 smk
Nice die but it wasn't the best cs. I did eventually receive a working die. 8 sizes in and no clickers but I do get the weird line above the web like most folks at matches I see running 300nm imp chambers.
I top out at 3060 with 87 gr of retumbo and the newer 230 smk
Have you tried it yet? I’m curious if there’s a measurable difference in accuracy/precision?
Also, how much is that die compared to a quality off the shelf?
-TIA-
Really interested in the Cortina Mandrel Sizing die. Sizing of the brass is the one thing about this cartridge that seems to be a PITA to get right. Very inconsistent if I would get a clicker or not. I have learned to bump it down 3-5 thou to get it to chamber and not all of the Lapua brass would do it either.
No, have not yet tried this custom die…it arrived yesterday.
I have been using Cortina’s mandrel expander dies for .300 PRC, .300NM, and 33XC. All do a nice job of sizing the case body to eliminate “clickers”.
I will report back once I’ve used Cortina custom sizing die.
As for pricing: contact Clay or Mitch at Cortina Precision.
I have been using Cortina’s mandrel expander dies for .300 PRC, .300NM, and 33XC. All do a nice job of sizing the case body to eliminate “clickers”.
I will report back once I’ve used Cortina custom sizing die.
As for pricing: contact Clay or Mitch at Cortina Precision.
I believe once you have a case that is giving you clickers you are not going to be able to get rid of it with a tighter fitting/resizing die, even a small die. Those will most likely prevent them but I don’t see it squeezing the web back enough. I don’t think a 7/8 die is thick enough for .585 cases also. Best to jump up to 1-1/4 dies. I’ve fought this same issue with the .338 Norma. Less die options for that too. The only thing that has cured clickers is the universal Rollsizer. F class John did a nice review on it. I saw it at shot show this year. Ended up buying one. And it’s legit. It works very well. It’s expensive but considering lapua 338 Norma brass is $400 a box now I justified it.
Did you purchase the hand crank RollSizer or the 110v powered model?
If you have the hand cranked version how laborious is it to base size 50 or so magnum cases in a session?
If you have the hand cranked version how laborious is it to base size 50 or so magnum cases in a session?
BC Micron bushing sizing die is back in stock.
