Note: As of January 29, 2015 this Group Buy is being produced by Swede Nelson at NOE. See post #146 for a link to the NOE Forum and the Group Buy for this design. If you signed up in the past on this Group Buy thread, and still want a mold, you must go to the Group Buy thread for this design on the NOE Forum and sign up there. We will not be carrying over the list from this site to the NOE Forum.
This is a Group Buy for the Badgeredd designed, 170 grn FNGC which will be produced by NOE. This design is for the milsurp 7x57's and commercial guns that their owners can verify one of the four size options will fit. This design is offered in four paired band/nose diameters as follows:
Option #1) .287" bands / .276" nose
Option #2) .289" bands / .278" nose
Option #3) .291" bands / .280" nose
Option #4) .293" bands / .282" nose
Click on the diagram to enlarge.
The skinny top grove just below the front band is not a crimp groove. It is a scraper/lube purge groove.
This design is meant to be lightly crimped on one of the drive bands. This works well when there is sufficient neck tension; that means the ideal sizing diameter will be .002" - .003" over groove diameter, no more than that is needed.
This boolit was designed to work best in Military Surplus rifles with throats that measure .300" to .725" in length. Long, worn out throats are not uncommon in Military Surplus Mausers chambered for the 7x57. Even guns that appear to have new, unfired replacement barrels exhibit throats that are over .300" in length. The throat of my 1908 Brazilian Mauser is .380" and this rifle looks to have never been fired after the last refurb at the depot. My 1893 Spanish Mauser produced by the Oviedo Arsenal in 1915 and reworked at least once since then has a .490" throat with a gorgeous, bright, sharp bore. There are also plenty of commercial rifles out there with long throats. If your rifle has a throat shorter that .300" understand that you will have some or all of the gas check protruding down past the neck. With crimp on gas checks (Hornady, Gator) there doesn't seem to be a problem here; but that is for each prospective buyer to decide.
Buyers must measure the throats of their rifles before committing to this Group Buy. This can be done with a pound slug, cerrosafe throat cast; or by the following quick & dirty method:
1) Measure the length of a casing and write that measurement down,
2) Insert a flat based jacketed bullet backward in the case,
3) Chamber that dummy round gently,
4) Extract the dummy round,
5) Measure the dummy round overall length now that the backwards jacketed bullet has been pushed further into the case.
6) Subtract the original casing length from the length of the dummy round. The result is your throat length.
Next, you must slug your barrel groove dimension. In Military Surplus Mausers brand new barrels seem to mostly run .286" to .288" in the grooves. But, there are exceptions even there. I have heard of grooves as fat as .291" so nobody should assume .287" for military or even .284" for commercial rifle grooves. My Ruger M77 MkII grooves slug at .285" and I have heard of commercial grooves slugging even fatter than .287"
Last of all, buyers should check their land height. This is best done with pin gauges. Start with the .276" diameter gauge. To do this insert the pin gauge at the muzzle. If it slips in over the lands it is too small. Insert the next higher pin gauge, and so on, until you get to the size that will not enter the bore. That is the minimum nose diameter that will ride on top of the lands properly. Just to be on the safe side here, insert the pin gauge into the chamber as well. Then gently tip the muzzle down so that it slides down into the throat. Basically you are making sure that the pin gauge doesn't slide down into the bore. Pull the bolt and use a flashlight to verify this. If it does slip down into the bore, gently push it out with a cleaning rod and try the next larger diameter, until you get a diameter that will not go down the bore. My 1893 Spanish Mauser suffers from this condition. So, I have to go to the next larger nose size option (above what the throat actually requires) to ensure the nose isn't flopping around or slumping as it starts into the bore. If the muzzle lands are worn down more than at the throat I would recommend that you go with the fatter diameter that the muzzle needs. So either way, go with the fatter nose diameter that is present at either end of the barrel.
Write that number down and check the four band/nose options listed above. Pick the nose diameter that is the closest to, but larger than the pin gauge diameter that would not enter your bore. Example, my Ruger M77 MkII accepts a .278" pin gauge, but will not accept a .279" pin gauge. That means I have to order option #3 (.280" nose) and size down to .288" on the drive bands for this rifle.
If you are worried that for some reason your rifle won't chamber or safely fire a boolit sized to .003" over your groove size just take an un-resized fired case and insert a pin gauge into the case mouth until you find the one that barely enters. Now subtract .001" from the diameter of that pin gauge. The result is the maximum safe diameter your rifle can handle allowing enough case neck expansion to release the bullet upon firing. I bet you'll be surprised just how "fat" a cast bullet your rifle will chamber safely!
Ok, so if you've gone through all of this, and you are still interested, here's how we will run this Group Buy. This is not going to be a 12 week Group Buy. Not because of Josh, it was my decision based on the fact I wanted all those members interested to have plenty of time to get their rifle(s) checked properly as described above. That means I am giving everybody time to beg, borrow, steal, or buy pin gauges so that they can check their bores and order the correct mold! I also wanted to ensure enough orders so that this deal will make it worth while for Josh financially based on all of the extra work cutting these molds will be for him; with four different band/nose options and gas check shanks that have to be cut separately. Therefore, this Group Buy will remain open until mid-July, 2014 at the earliest; and probably run until the end of August, 2014 When it closes I will post on this thread and Josh can decide at that time how he wants to take payment but I think money order has been preferred by him in the past.
These are the mold/cavity options available: Check the NOE website for details.
All who are interested in ordering on this Group Buy please post on this thread and I will keep a running list in post #2 of who wants what diameter mold as well as how many cavities, etc.
Badgeredd and I have done our best to come up with a design here that will fit as many of the Military and Commercial 7x57's as possible. If you intend to order a mold(s) please follow the above directions to ensure that you have a boolit that will actually fit your gun. Otherwise it won't shoot any better than the undersized options from the major makers that have always shot poorly out of most everybody's 7x57 rifles.
As far as 7x30 Waters, 7mm-08's, .280 Remington's, 7mm Rem. Magnums, 7mm Weatherby's, and all the host of new long and short mag 7mm's I have no idea if this design will be of use. It is up to the potential buyer to determine if this design will fit and work in his rifle.
I will do my best to answer any questions that may come up.
Thanks for looking,
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Originally Posted by brotherdarrell
