Sizing brass for a tight chamber

SuperCub

SuperCub

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I recently bought a BRNO 6oo in 30/06 and had it bedded, floated, and trigger done. I finally got around to shooting this week and had planned on using some spare, once fired brass I had on hand. Before loading, the brass was, cleaned, FLR, trimmed to length, and cleaned again to remove lube. Once at the range, I found pretty much most of the reloads were tight while chambering, but was able to shoot and extract all of them. Some were very hard to extract, but again, most were just tight coming out.

I then decided to borrow a set of small base dies (Thanks Billy the Kid :D) and resized the brass I had on hand using them, but tried the brass before loading. Again, it was tight, not much better than the regular dies. :confused:

So now I head off to CTC and WalMart to buy some WW factory ammo. WalMart has NO 30/06, but that is another rant. :mad: CTC has a few Rem and WW loadings, so I get 2 boxes 180gr Silvertips to the tune of $60. :mad: :mad: These seem to chamber just fine.

Question ....... Will this new brass work OK with just neck sizing with regular dies or will the SB dies still be required? I'd much prefer to neck size only and the SB dies are borrowed.

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Do have a cartridge gauge to check the headspacing of your FL sized cases? Maybe they need to be sized a tad more.

Your new brass will form to the chamber dimensions, then spring back a little. You should be fine with neck sizing only, at least for a while, unless you're shooting nuclear loads.
 
TRY: When full sizing, make a full stroke...turn the brass 1/2 turn and make another full stroke without letting the expander die come out of the neck (just to reduce the expand/contract cycle on the neck.
Quite often, it is necessary to full size brass and trim after the first firing. After that, neck sizing only should work for several reloads.
 
JEC said:
TRY: When full sizing, make a full stroke...turn the brass 1/2 turn and make another full stroke without letting the expander die come out of the neck (just to reduce the expand/contract cycle on the neck.
Click to expand...
I suppose the would remedy any case that is out of round. Good idea.


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It may just be that the brass neck is too thick and it expands a touch when you seat the bullet, brand x may have thinner necks and they fit better. If this is the case you can either; outside neck turn or ream inside case necks,or use the only brand that fits. This condition is only an outside chance, try the other remedies first. Some match chambers will not allow any case to enter without reaming/turning.
 
take an unfired factory round, and put layers of scotch tape on the base and see what thickness it will allow.

then you will know if it is a minimum headspace issue or a diameter issue.
 
SuperCub said:
I don't have a gauge, but I don't think headspace would be an issue, given the tight fit.


As noted, the cases were FLR in regular dies and then SB dies. Both sizings were too tight.

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30'06 headspaces on the shoulder, right? If the shoulder is too far forward, the cartridge will be a tight fit, because it's slightly longer than the chamber, and require a lot of bolt pressure to close. Since you tried SB dies and have the same problem, I can only assume that the bases of your cartridges aren't too big, it must be something else. HS would be a good thing to check.

Try screwing your FL sizing die down another quarter/eigth/sixteenth of a turn and see how well the empty case chambers.
 
rgv said:
take an unfired factory round, and put layers of scotch tape on the base and see what thickness it will allow.

then you will know if it is a minimum headspace issue or a diameter issue.
Click to expand...
1 layer is OK, but it seems to tighten up at about 2-3 layers.

I'm not really sure what that means. :confused:

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I have a spare shell holder for just this occasion. I took the shellholder and placed it upside down on a piece of sandpaper and removed about 3 thou off the top of it. I sanded the holder on a flat surface and measured every few minutes till I got the correct amount of material removed. When your FL die is set up as far as it can go,this "shaved" shellholder allows the brass to go further up inside the die without crushing the case.
My Brno 7x57 was tight chambered and this fixed it, also I have had a couple of custom 308's where the custom shellholder worked on too.
 
SuperCub said:
1 layer is OK, but it seems to tighten up at about 2-3 layers.

I'm not really sure what that means. :confused:

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Click to expand...

only one layer of tape on an unfired case is pretty tight.

now try it with one of the fired cases that has been FL resized. If it will not close at all with one layer, then go to the trimmed shellholder like 303carbine suggests and keep bumping the shoulder back until a case will chamber. you probably have a chamber with headspace on the low end, and dies on the high end (which almost all are).

If it will close with tape on the base, then it is not a headspace mis-match between the chamber and dies, it is a diameter mismatch, and trimming the shellholder won;t work.
 
rgv said:
now try it with one of the fired cases that has been FL resized.
Click to expand...
It got tighter with the layer of tape, but would close with extra force.

rgv said:
If it will not close at all with one layer, then go to the trimmed shellholder like 303carbine suggests and keep bumping the shoulder back until a case will chamber. you probably have a chamber with headspace on the low end, and dies on the high end (which almost all are).
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I tried the trimmed shellholder and found it worked pretty reliable at about 0.005" removed from the holder. The cases go in and out easy. It also works well with both the regular and SB dies.

Looks like that has it fixed. I'm gonna fiddle with more, later this evening and to the range in the morning...... I will update with results.

THANK-YOU VERY MUCH!! :D

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One other fix for the problem above is to make a washer or two out of shim stock that will fit under your case in the shell holder, you'll have to try dif. thicknesses but there usually is alot of play with those shellholders.
 
I have two Factory rifles with those slightly "tight" chambers. I solved the problem by chucking the FL sizing die in the lathe and trimming .005" off the bottom of the die with a carbide bit. Works perfectly now, and means I can use my shellholder as is. Regards, Eagleye
 
Eagleye said:
I have two Factory rifles with those slightly "tight" chambers. I solved the problem by chucking the FL sizing die in the lathe and trimming .005" off the bottom of the die with a carbide bit. Works perfectly now, and means I can use my shellholder as is. Regards, Eagleye
Click to expand...

Hes got the idea.
Might need to just bump the shoulder back a hair more.:D
 
mikeelliot said:
Hes got the idea.
Might need to just bump the shoulder back a hair more.:D
Click to expand...
I don't have a lathe here to trim back the die, so it was much easier for me just to thin thin the shell holder. Both methods would give the same results and now I can just choose which shellholder to use according to the rifle.

No further results to report today as it is too windy here today and our range overlooks the Bay of Fundy, so it would be near gale force out there. :(


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Finally got back out to the range today with the re-fitted brass. All cases fed perfectly and would easily go back into the chamber as is. Later, I neck sized it and as expected it worked perfectly. Problem solved. :p

Got some nice groups while I was at it .... BRAG/BRAG/BRAG :D

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