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View Full Version : Setting headspace--maybe went too far



rockrat
12-16-2008, 01:20 AM
Put together a 260 Rem on a 700 short action with a Model 7 barrel. Headspace was too great, so tried correcting this on this AM on the lathe.

Calculated I needed to turn the barrel about 35 degrees for zero headspace, took it a bit at a time, but went a little too far(maybe 40 degrees) and got to probably minus .001 instead. I can close the bolt, but it is snug and rubs the head of the brass so it is bright a little..

Thinking about lapping the lugs a bit and figure that this will change the headspace enough to get rid of the snugness or I could just run my reamer in to correct things. Only drawback with the reamer is that the chamber is nice and snug as the fired case will hold a bullet with a little light pressure. Figure bullet clearance upon fireing is probably .002" at most.

What are your thoughts

hornsurgeon
12-16-2008, 01:34 AM
if it were mine, and i was to handload for it, i would leave it. the brass will be fireformed and fit fine for neck sizing only. if it were for someone else or if i planned on using factory ammo for it, i would ream the chamber.

jhrosier
12-16-2008, 06:28 AM
...What are your thoughts

I would take about .003" off the top of the shellholder.
Paint it bright red so that you don't accidentally use it for another gun/caliber.

Jack

rockrat
12-16-2008, 09:49 AM
Instead of the shellholder, I might just take the .003" off the bottom of the sizing die.

Its my gun and I will handload for it. Now I can put to good use the 6.5 mould I bought last year!!

Thanks

deltaenterprizes
12-16-2008, 04:15 PM
Did you allow for .002'' crush when you tighten the barrel?

rockrat
12-16-2008, 06:24 PM
Allowed for crush, just took a little too much off the shoulder of the barrel.

deltaenterprizes
12-16-2008, 07:13 PM
Are you using a headspace guage or a loaded cartridge?

rockrat
12-16-2008, 08:19 PM
No-go guage and a cartridge also(firing pin removed)

deltaenterprizes
12-16-2008, 09:16 PM
One pass with the reamer by hand and I think you will be right on. Hold the barrel pointing downward and use light pressure,if you have an extension you don't even need to remove the barrel from the action.

Molly
12-17-2008, 07:58 PM
Old timers trick: Take the barrel off and peen the shoulder lightly and uniformly, all around the circumference. Replace and tighten. You will have no further problem. Cure is permanant too.

Molly

deltaenterprizes
12-17-2008, 08:15 PM
How about a thicker recoil lug or a .002'' shim?

Three44s
12-30-2008, 02:08 AM
You mentioned lapping the lugs?

I would try that on a limited basis and see if you end up spot on first.

Three 44s

Willbird
01-05-2009, 01:50 PM
If I had just one headspace gauge to pick I would buy a "go" not a no go. I prefer to chamber for a "feel" on a go gauge, this means if I handed you the rifle you could tell me with your eyes closed if there was a gauge in there when you closed the bolt, this works out to .000 endplay on the bolt with a "go" gauge. Purely hunting rifles I shoot for .002" endplay.

Many sizing dies and shell holders will not actually bump the shoulder on a fired case back to minimum saami, the makers do this as a safety factor I think.

I prefer to alter and mark shell holders rather than dies, because different brass will give you a different shoulder bump, and you will in my experience get MORE bump after you anneal the case necks.

Redding sells "competition" shell holders which are marked in increments to bump the shoulder more, this is nice because you can write down a setup and return to it.

One other thing you can do to actually check the headspace on your rifle is to loosen the barrel, and then put the "no-go" gaube in the chamber, and tighten the bbl by HAND and don't be a gorilla about it :-)....then measure between the front of the receiver and the recoil lug (if it has one) with feeler gauges....this will show you the actual difference between your chamber and the "no-go" gauge.

Bill