Case Trim help

R

R700

CGN Regular
GunNutz
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Greater Vancouver Area
new to this reload stuff. got the rockchucker kit. I use the rcbs neck size die to necksize my fireformed hornady match brass. After i neck size i measure the brass before i trim and i find variances in each brass. Usually ranging from 2.014-2.008. The max for the .308 is 2.015 and the min is 2.005. When I use my rcbs trim pro manual trimmer, I find 2 things are happening. First, the pilot caliber doesnt fit smooth in the case mouth and I have to push the handle down to get no resistance from the pilot caliber inside the case mouth. 2nd, I find that the brass trims not uniformly and leaves a bit of a groove where the pilot trimmer sits inside the case mouth. I've tried reseating the trim shell holder and the pilot caliber but the only way i can keep the case level with the cutter is by holding down the handle. Anybody see this before or is this a one of kind thing.

2nd part, if i decide to use the brass not trimmed which ranges from 2.0014 to 2.008, what kind of issues come into play. Accurate target shooting is my goal. Thanks.
 
Seems i am figuring it as i go here but if anybody has experienced the same thing could you please let me know. Instead of just neck sizing i tried a dummy round with full length sizing and it loaded in my chamber smooth. I am loading for a 5r milspec with hornady match brass, varget, federal 210 and hornady amax. Dummy load is just the bullet and brass of course. But it seems that the fireformed brass is too big for the chamber. Anybody experience this?

The trimmer still does the same thing.I found somebody else with the problem and they said this "Cutter Shaft has excessive runout which causes the pilot to run a groove on one side of the inside of the case necks. Due to the runout, the cases cannot be trimmed square. Have friends with the same trimmer that don't have this problem. Possibly just got a bad one?"
 
I can't chamber fire formed if it was fired while my gun was realy hot. Steel expands as it's heated, I believe the chamber grows just enough that the brass forms to that size, then when it cools and shrinks that case won't fit. I don't know about you but I like shooting, not waiting for the barrel to cool, I trade off some accuracy and full length resize, but my chamber is quite tight to begin with.
 
Are you using brass from different manufactures.....or headstamps.....or from a different lot.......or different amounts of firing?

All these factors will play a roll in how much brass is in the neck of a particular piece of brass!
 
kinda thinkin what fuzzynutz is saying. I fire 5 shot groups. I don't wait for the barrel to cool down. 5 shots by single feeding into the chamber. After 5 i let it cool completely. I am using a 700 5R Milspec. I use the same lot and the same brass and that has been only fired once. When i chamber the round after neck sizing it hangs up half way through the throw of the bolt than it feeds than the bolt hangs up at the end of the throw. If i point the barrel straight down and feed a round into the chamber it fits but won't extract. I am thinking that the brass case has expanded too much from the first cycle of the brass at the bottom near the rim and near the shoulder. I full size it and it feeds and cycles no problem.I use the rcbs fl die and neck size. I am trying to figure where the problem is and i think it has to do with the body of the brass. Any remedies. Cheers and thanks for the input.

As for the trimming, I am no longer using the rcbs trim pro and now using a Lyman Universal to see if the pilot still grooves the inside of the casing. I will let you know about that.

Scoreboard: Lyman Universal trimmer 1
RCBS Trim Pro 0

The Lyman Universal Trimmer trimmed the brass uniformly with no grooves from the pilot on the inside of the case mouth. RCBS not so much. Rare problem but I am happy now that the brass is cut to spec and no grooves.
 
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