Neck clearance ...

[Con]

Guys,
Need some thought provoking responses. What's an appropriate neck clearance for a precision varmint rifle? Just measured one of mine at 0.008" (fired = 0.203" less loaded = 0.195") which to me seems too much and more in tune with a big game rifle. Cases had been turned, need to check whether it was to fit the chamber or just sort out inconsistencies, but I'm considering working at quartering the figure to a 0.002" clearance if possible ... any negatives to that or something I haven't thought of?
Cheers...
Con

[adamjp]

My experience with several neck turned cases suggests that I want 1.5 to 2 thousands of an inch on each side.

That is a clearance of 3 to 4 thou for the whole neck. I have done tighter, and certainly wouldn't go under 2.5 thou. Pressure problems always come if I go tighter.

[dg]

at least, .003" overall or .0015" per side to allow for some projectiles that may be "fat" and also to allow for residue build up in the chamber neck area.

cheers
dave g

[chris.tyne]

Con when you take into account brass spring back it would be more like 0.009 clearance.I run very little clearance on mine ,0.0015 on my PPC's and 0.002 on my BR's,I have run fitted necks and I decided it wasnt worth it to me.
Having said that I have run near 0.004 clearance in one barrel..............because I stuffed up and it made no difference that I could see on a target but I was sizing the neck more than I wanted.
Now supposing your dies are a good match to your reamer/chamber then you can run as much clearance as you like really,only thing is the extra work hardening of your brass,accuracy should be the same.....problem is not all dies are created equal.
Con a little wriggle is ok,a lot .....not so good,everyone is different,I do agree that 0.008 is more than I would like.


Regards Chris.

[Teepee]

As others have indicated, .008 seems a bit excessive to me.
I try and run with .003 for all of mine.
But that was what was suggested by someone more knowledgable than myself when I first went down this reloading path some time ago.
If it was me I think I would be trying to get closer to .003-.004" if possible.

[trevort]

As others have indicated, .008 seems a bit excessive to me.
I try and run with .003 for all of mine.
But that was what was suggested by someone more knowledgable than myself when I first went down this reloading path some time ago.
If it was me I think I would be trying to get closer to .003-.004" if possible.

How did you do that Teepee, you just typed word for word what i was thinking!

[Teepee]

Just lucky, I guess

[Con]

Con a little wriggle is ok,a lot .....not so good,everyone is different,I do agree that 0.008 is more than I would like.

Thanks Chris,
This is in my 17PeeWee ... I feel that 0.008" is to much, so will try forming brass to see how it goes in its virginal state. If it doesn't fit, I'll try turning for 0.004" clearance. Not too distant future, I'm hoping to have inline neck and seating dies made with the reamer to bring everything to as close to minimums as possible.
Cheers...
Con

[Aussie steve]

Con that big .17 of mine was cut so close, that I didn't have to size the cases, there is enough spring back in the brass to provide the right neck tension. That worked OK for me, though as I wasn't turning the necks so I couldn't change brands of cases in case they were a bit thicker.

[Con]

Con that big .17 of mine was cut so close, that I didn't have to size the cases, there is enough spring back in the brass to provide the right neck tension. That worked OK for me, though as I wasn't turning the necks so I couldn't change brands of cases in case they were a bit thicker.

Yeah ... 30Carbine cases are so common that leaving some clearance will be needed as I'm forced to use military, Winchester, R-P and PMC as located. If I go really tight tolerances, it'll be on selected cases that have been prep'd.

Fiddly little case ... 0.2gr took it from slightly stiff bolt lift to pierced/leaking primers. So backing off and re-evaluating.
Cheers...
Con

[Camel]

I finally managed to get hold of some new factory WW 30M1 brass yesterday, three boxes of 50 for 25.00 each, I had been on a waiting list with QGE for nearly 2 years, its amazing what you find on this internet thingo. No I didn't get them in QLD but from a shop in Melbourne. Pity they don't have any more.

[stinkitup]

I have a box of unformed cases not sure what brand winchester or pmc I think. If you want to swap so you have all the same as the mmj needs to be turned anyway.

Ryan

[Con]

Damn you Camel!

Never mind ... have x150 once fired cases winging their way to me, plus another x300 loaded 30Carbine coming. Picked up another x41 loaded Winchester 30Carbine today ... people give them away.

Should be enough ... maybe.
Cheers...
Con

[Camel]

Ryan, thanks for the offer mate, my original brass I got with the rifle is WW so these new ones will fit in nicely.

Con, I was watching a post you put up somewhere about your PeeWee, and someone gave the link to their website specials list, cant remember who or which gun shop, but I did get the phone number and jumped on them.
I've got a mate here who used to run an M1 years ago and he reckons he has 5 or 6 hundred new loaded ammo, somewhere in his 40ft storage container, as you can only get in the front four ft of it, he isn't really rushing to go rummaging around in there looking from them for me. Dunno what gets into some people, eh, you would think he would put in an effort.

[Branxhunter]

I finally managed to get hold of some new factory WW 30M1 brass yesterday, three boxes of 50 for 25.00 each, I had been on a waiting list with QGE for nearly 2 years, its amazing what you find on this internet thingo. No I didn't get them in QLD but from a shop in Melbourne. Pity they don't have any more.

Melbourne Firearms Centre - I saw them listed in there specials section last week.

Marcus