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Discussion Starter #1
Greetings to all... I recently acquired a No. 4 MK1, and I think it may have headspace issues (the bolt, stamped "0" has more than 20 degrees rotation). It seems otherwise in fair shape, and I'd like to fire it. Any advice on how to proceed?

Thanks in advance for all replies...
 

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What leads you to believe that you have a headspace problem? Also, what do you mean when you say the bolt "has more than 20 degrees rotation?"
 

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Don't know that there's any fix for bolt head over rotation short of a new bolt head. You might try a number 1 (pretty common), and see if that doesn't correct the over rotation and tighten up your headspace just a bit. You'll have to make sure that your striker protrusion remains within spec (.040-.050).

IMO, it's best to make the smallest adjustments you have to in order to bring all the component parts into blissful coexistence. :D
 

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We were all n00bs ourselves once.

First, here is a great page that explains about headspace

http://www.cruffler.com/trivia-October99.html

Now for the part that is relevant to you from that page

In another example, the SAAMI specification FIELD REJECT gauge for the .303 British is .070." However, the British military maximum headspace length gauge is .074." In this case if one had a British military rifle with a headspace measurement of .071", and for the sake of argument, British military ammunition, but used SAAMI specification gauges, one might be convinced that a perfectly serviceable rifle had excessive headspace.
So in your tests, closing on .07 is still okay and not closing on .08 (way excessive headspace) is correct.

Other useful sites

http://www.arrowmark.com.au/arrow5-1.htm
http://www3.sympatico.ca/shooters/Hometools.htm
 

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Discussion Starter #6
...
You might try a number 1 (pretty common), and see if that doesn't correct the over rotation and tighten up your headspace just a bit...
I'll bet there's a relatively easy way to get those.
Thanks much for all the info.
.
Anyone else?
 

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Bolt Heads

Hammerbach

An Armourer or a Commonwealth gunsmith would have many new and used bolt heads to chose from to cure the over travel problems or over rotation past 20 degrees. (see attachment #1) The photo is from a missing forum member from New Zealand and his gunsmiths supply of No.4 bolt heads.

Your posted photos are very small but there is a possibility that your bolt might need to be replaced because of wear due to the over travel or over rotation. (See attachment # 2) This composite photo shows one bolt and four different bolt heads, two of the bolt heads are new and unused, this bolt is no good and belongs in the scrap heap. (The 20 degrees is viewed from the rear not the front)

In a perfect situation the new bolt head should not line up with the right locking lug (under rotation) and it would need to be worked in or broken into the bolt to fit. Below (attachment # 3) is a photo of a bolt being fitted on No.1 with a bolt head spanner, the spanner handles were worked back and forth (righty tighty-lefty loosy) until the bolt head aligned with the right locking lug.

The best place to shop for Enfield parts is at SPRINGFIELD SPORTERS http://ssporters.com/enfield4.htm
Item 6D BOLT HEAD SIZE “1”, NEW
 

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Hammerbach,
Finding someone qualified to look it over, may be much harder than learning to do it yourself.

It is not difficult, just read the great info posted by Ed Horton.
 

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Discussion Starter #10
Sorry, I didn't mean I was giving up. Not afraid to try (I've built telescopes, musical instruments, tools for my shop), but the consequences of being wrong worry me. I'm going to get another bolt head and see if it will fit, but I'm going to have to get someone more qualified than me to see it before I fire it.

All resposes are much appreciated. Thanks, guys...
 

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Its easy as pie

Hammerbach

When your bolt head is delivered to your home please remember this.

  • Approximately 75% of bolt wear is between the two mating surfaces of the bolt body and the bolt head.
  • It is possible when going to a larger number bolt head to end up with more headspace.
  • The “new bolt head” after firing 50 to 100 rounds will “break in” and “seat” to the bolt body and headspace can increase a few thousandths.
  • If the bolt head is a tight fit and will not align with the right locking lug, (close fully) with the bolt head attached to the bolt body, place the “bolt head” in a padded vice, tighten the vice and work the bolt handle right and left. This breaks in and “seats” the two mating surfaces and is the poor mans “bolt head spanner wrench”.

Attachment # 1, new bolt head may be a tight fit and not align with right locking lug.

Attachment # 2, breaking in the new bolt head so it will align with locking lug.
 

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Best way to fix problem

Great tips all...:D
 
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