WTK bolt head lengths for the various sizes, No4 rifles

[Prairie Fire]

I was wondering what the lengths of the No 4 bolt heads are, sorted out by 0, 1, 2, 3. Plus or minus on the lengths, would be helpful.

Reason I ask, is because I'm reloading for the cartridge, and have three rifles with variously sized chambers and am looking for case life. I realize that the correct thing to do, is to segregate brass by rifle, and keep it segregated. But, while trying to sort out how much to resize in order to have easy chambering in the shortest chamber, I may have found an excessively long chamber in one of the rifles.

The suspect, is a 11/53 Fazerkerly which showed little use when I bought it fifteen years ago. Has a #2 bolt head on it. I can put a target paster on the head of South African ball ('70s) and close the bolt with no final resistance. I can chamber spent cases shot from my tightest chambered rifle into this one, and close the bolt with no final resistance.

Where I live, the couple of gunsmiths do not have .303 headspace gauges.

I was wondering if trying a 3 bolthead on the long chambered rifle might be helpful. Easy bolt closing on a target paster/over ball, might say that the headspace on this rifle might be long. Doing this, might help rein in the herd on brass elongation. Thoughts?

This is my first post here. For some years, CSP seemed to be unfindable by me after it went away. But CSP was where I learned of 9/11 one morning.

Thanks for any help. Anybody that wants to talk or give advice on .303 reloading, I'm all ears.

[C5M1]

There was a long thread about this on the old csp. A lot of input from the forum members, measuring lengths of different size boltheads. They varied quite dramatically. Personally would not go by the size, but by measurement. hth

regards dennis

[John Sukey]

All I can say is that a target paster on the back of a case is NOT a headspace gage. Also the thickness of cartridge rims can vary. Especialy between U.S. and British cases. U.S. ones are mostly thinner while HXP brass and South African is spot on.

[Scott from Indiana]

I once had a similar idea, to resize my cases just enough so that they would chamber in all of my Enfields, without fully/excessivly resizing them. It turned out that several of the rifles needed the cases fully resized to easily chamber. However, I had more rifles than 3 to adjust for.

If you compare your fired cases next to each other, you should be able to compare the lengths of the chambers by how far the shoulder is moved forward. I suspect that you will find that the "long chambered" one moves the shoulder much further forward than the others, much more than you could make up for by adjusting headspace.

Maybe you could get by with segregating the cases for the rifle with the long chamber? I just ended up full length sizing all of the brass, shooting mild loads and discarding them when they start splitting.

I apologize in advance if I am not supposed to do this, but there is bolthead information here for you: http://forums.gunboards.com/showthread.php?139998-Bolt-Head-Survey-Results-Conclusions-amp-Suggestions

[Doug Rammel]

Get a field gauge.

http://www.okiegauges.com/

Keep your brass segregated and just neck size the brass when you reload. That will give you the maximum number of reloads for your brass.

Invest in a digital caliper. They are not that expensive. You need one to figure out the size of your bolt head. The numbers 1 to 4 don't tell you anything. Use it for OAL and case length also. :icon_sunny:

[John Sukey]

Just a small add, The rifle could have left the factory with a No.2 bolt head. The workers simply tried different bolt heads until they found one that met the specs. So you could have a NEW rifle with anything from a 0 to a 2, possibly even a 3

[Prairie Fire]

Thanks to everyone, particular thanks to Scott in Indiana, who gave the whack upside the head without actually saying it, that chamber length variation and rimmed cartridge headspace are two different things I thank him also for his link to the confusion of the measurement of bolt heads. I'd not been sold on the factory stamped gross numbers to begin with, as something other than to put out headspaced rifles. Measuring my three boltheads, I found them hard to measure due to the big radius on the threaded side. Also noticed a bright circular area on one which would not normally be in the caliper-measured area, but I guess that bright spot is where rubber meets road. Advice given to buy calipers is appreciated, I've been using Chicom RCBS steel calipers for everything for some years.

I will be doing the brass segregation-by-rifle thing. Had hoped to avoid it, but the avoidance of doing so is not a smart thing.

[Sunray]

"...chambering in the shortest chamber..." If you're using the same brass in more than one rifle, of any kind, you have to full length resize when loading.
"...might say that..." It says nothing.
Nominal bolt head dimensions are here. However, don't just change the bolt head unless you have headspace guages. http://www.enfieldrifles.ca/ti3.htm

[Scott from Indiana]

You are welcome! I have learned a lot here and on other websites, please share what you learn with fellow shooters in need of info. I will only add that I have never regretted my purchase of a .303 "field" headspace gauge. If you have even a passing interest in any additional Enfields, it will be a purchase that pays you back.