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Char-Gar
09-09-2006, 12:53 PM
OK... I have just finished preping a dedicated lot (80) of 30-06 cases for cast bullet loads in my feaux NRA Sporter. I started with once fired full snort condom bullet loaded cases (LC 68 Match) and drilled the primer flash holes with a #28 drill. I neck sized and trimed to a uniform length (2.486). I filled the case head lettering with red nail enamel.

What is the velocity/pressure limit with the flash hole drilled cases before I get on thin ice? I am talking sacred silver bullets here and not those dreadful little yellow thingies.

felix
09-09-2006, 01:42 PM
Chargar, that is an ignition question, and is hard to determine which is OK-right, barely-right, or just-right. Look at the target, and make adjustments using a primer lot that you have tons of individuals left. In general, alter the primer choice first to fine tune a load that shoots day in and day out throughout the year. Increasing the flash hole diameter is equivalent to making the powder burn faster, especially up front. Go to a slower powder if you open a hole too much for your favorite load, after picking a cooler primer that does not work. ... felix

Char-Gar
09-09-2006, 02:10 PM
Felix... I am pretty well comitted to the Remington 9.5 primer as I have a large quanity of them. I realize the powder charge may have to be tweaked.

My main concern is getting the pressure to a point that the enlarged flash hole become a danger. Safety is the thrust of my question and not accuracy. I should have been more clear with that.

felix
09-09-2006, 02:13 PM
In that situation, find the largest primer hole you have amongst the cases, and go one letter size larger so you can just smooth them up to the same diameter each. ... felix

Bass Ackward
09-09-2006, 02:16 PM
Oh my God!

Yep. Just like Felix says. Opening a flash hole speeds up pressure considerably and it isn't predictable. What it does is magnify bullet weight changes. Common loads that worked before might have to be lowered considerably with the same powder and then over all velocity will be less.

You probably won't be able to shoot 2400 anymore, but 4831 is going to seem like it with a 210 grain bullet. Might work great with some of that R E A L slow surplus stuff like 860 and 872. And because presure is going to spike quickly, you will likely need a harder bullet. Especially if you want to leave the cast safety zone velocity wise.

eka
09-09-2006, 05:19 PM
I filled the case head lettering with red nail enamel

Thats a new one, what was that step for Charger?

Keith

Char-Gar
09-09-2006, 05:44 PM
I did it so I could tell the cases with drilled flash holes from others who have not had the flash holes opened up.

StarMetal
09-09-2006, 06:50 PM
I mark the very edge of the rim of special loads, or should I say special brass, with my checkering file. It leaves nice little teeth that, unlike nail polish or marker pen, doesn't wear away.

Joe

catkiller45
09-09-2006, 07:00 PM
I never do this unless shooting black powder..Smokeless has too much pressure and will blow the primers out.Slaming them up aganist the bolt face.Not good..

keeper89
09-09-2006, 09:17 PM
Just to add my .02 to this.....have never tried drilling out flash holes but I do use a flash hole reaming tool on the brass I plan to use for serious accuracy--it sure is surprising how much brass actually does have a burr or burrs on the inside of the flash hole.....

felix
09-09-2006, 09:40 PM
Yeah, for the BR gun only in my situation. It would be nice if the case making folks punched out the pocket from the inside of the case, and then cut the flash socket out to proper depth (and width) which would cut off the burr. Only the real accurate guns in my house get quality cases, such as the new Nosler line. These cases are superior in every respect, most especially in terms of brass thickness. I found the same quality with BlackHills cases, but gave up trying to find them. ... felix