No.4 Mk.I vs. Mk,I* bolt-heads

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bradtx
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No.4 Mk.I vs. Mk,I* bolt-heads

Post by bradtx » Mon Jun 06, 2005 11:01 am

All, Because I think the major reason for chipping of the slot on Mk.I*s is an incorrect bolt-head I'm presenting a pic of the differences...





http://img.photobucket.com/albums/v11/bradtx/bh2.jpg" style="border:0;"/><!--EZCODE IMAGE END-->





The one on the left is from a '42 Faz, the right a '50 LB because these two photographed the best. The big difference is the beveling of the Mk.I* bolt-head, fore and aft in the rail slot to transit the slot without jumping out.





Regards, Brad<!--EZCODE EMOTICON START :tex --><img src=http://img.photobucket.com/albums/v51/N ... all/Tx.gif ALT=":tex">;

<p></p><i>Edited by: <A HREF=http://p089.ezboard.com/bmilsurpafterho ... >bradtx</A> at: 6/6/05 9:03 am

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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by dromia » Mon Jun 06, 2005 3:06 pm

Hi Brad,





thanks for that most intuitive of posts, some people would say that your are a sad bastard looking at things in that amount of detail. :lol:;





Presonally I think it demonstrates a well rounded, right thinking inquisitive Enfield mind which is the best there is.





Thank you for sharing your perceptive insight and evidence, this was no doubt obvious to those who made Enfields and it is our joy/duty to rediscover these important nuances of manufacture.





I've copied this post to the temporary forum as protection from any Ezboard restore so please look there for replies. :D;

<p>http://www.photobucket.com/albums/1003/ ... _Badge.gif" style="border:0;"/><!--EZCODE IMAGE END-->





Adam.





Why don't you visit .





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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by Guest » Tue Jun 07, 2005 6:25 am

Nice observation, Brad.





If I remember, last summer when I put a No.1 bolthead on my Mk.1*, I eased the leading and trailing edges of that rib slightly with a triangular oil stone. It seemed like it needed it. Must be a Mk.1 bolt head, I'll have to check.





MM

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brewstop
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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by brewstop » Tue Jun 07, 2005 4:55 pm

Apart from different factory manufacturing tolerances, I don't think that there was ever a different type of bolthead between Mk1 and 1* rifles. If you examine the military vocab lists, only one type of bolthead is listed, with a different part number for each of the four usual sizes. They would have listed seperate part numbers if there were two models of bolthead - other parts where there is a model variation (safety catches, cocking pieces, bands, etc) all have seperate unique numbers.





There are manufacturing variations, but there does not seem to be a statistical pattern by factory of origin. I have about 50 boltheads on and off rifles, and the shape of the lip is fairly random across the six factories that made them. Some of my rifles were in the grease from FTR, and the boltheads are mixed between Mk1 and Mk1* rifles (eg Savage bolthead on a BSA rifle), which wouldn't have happened if there was a military specification to the contrary.

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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by Niner » Tue Jun 07, 2005 9:37 pm

Article in the recent shotgun news of the Savage MK1* says this about the bolt head.





<!--EZCODE QUOTE START--><blockquote><strong><em>Quote:</em></strong><hr>The bolt head was modified, in addition to the means by which it was guided and retained. The extractor lug was decreased in size, and instead of engaging over the edge of the right receiver wall,it now moved in a groove milled inside the wall...<hr></blockquote><!--EZCODE QUOTE END-->





This was in an article entitled, " The World's Best Turnbolt Infantry Rifle: No. 4 Enfield", by Peter Kokalis.





My Savage 4MK1* came with a bolt head with the splayed bolt groove edge and it would jam in the bolt guide groove slot. I replaced it with one of the more regular looking bolt heads like is shown in the picture. It functions a little better now, after also working on the track opening with a file to smooth out the edges..





Although the magazine piece thought the Mk1* design stronger on a number of points, I think the Lend Lease weapons were of lesser quality than the Brit manufactured ones... just my 2 cents worth. I think the cheaper track opening near the receiver only made the bolt more likely to jump the track enough to hangup when loading. Although, the instructions were to move the bolt forward smartly and with a quick movement. Couldn't be because of the possible hangup , could it?:D;

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http://pic11.picturetrail.com/VOL384/10 ... 430766.jpg" style="border:0;"/><!--EZCODE IMAGE END--></p><i>Edited by: <A HREF=http://p089.ezboard.com/bmilsurpafterho ... s>Niner</Ahttp://x9eralpha.home.comcast.net/85.gif[/pic] at: 6/7/05 7:44 pm

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brewstop
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boltheads

Post by brewstop » Wed Jun 08, 2005 5:22 am

But that article just goes to show how urban myths start! Its actually referring to the difference between No1 rifles and No4 rifles!




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Re: boltheads

Post by Niner » Wed Jun 08, 2005 9:20 am

You're right brewstop the comparison is to the 1MKIII as to the bolt head design and function. I should have made that clear. But....what urban myth?





You don't mean the title, do you? :lol:;

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http://pic11.picturetrail.com/VOL384/10 ... 430766.jpg" style="border:0;"/><!--EZCODE IMAGE END--></p><i>Edited by: <A HREF=http://p089.ezboard.com/bmilsurpafterho ... s>Niner</Ahttp://x9eralpha.home.comcast.net/85.gif[/pic] at: 6/8/05 7:25 am

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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by bradtx » Wed Jun 08, 2005 10:26 am

Adam, I wish I could take credit for noticing this, but it was mentioned by someone else, somewhere and poo-pooed by the experts. <!--EZCODE EMOTICON START : --><img src=http://www.ezboard.com/images/emoticons/ohwell.gif ALT=":">;





brewstop, I couldn't find <!--EZCODE ITALIC START--><em>any</em><!--EZCODE ITALIC END--> documentation about a differently spec'd bolt-head for the Mk.I*s either, but concluded I just hadn't looked in the right place, yet. The beveling of the bolt-head seem to be a practical application change for N.A. production which didn't effect the interchangeability of N.A. parts onto the British rifles, dependant on how the original contract was worded. ;) (Come to think of it, are the sears interchangeable?)





MM, I think filing/stoning to the rails and bolt-head to be the only proper way to fix a rifle that has had problems in the smoothness of it's bolt operation.





Niner, I think the 'smartly operating the bolt' had more to do with getting the empty case out of the bolt-way and overcoming the resistance of the cocking upon closing design.





Hopefully the artical will help prevent further slot problems in Mk.I*s and hopefully someone with a larger collection than I can do a 'stare and compare' and report. BTW, my <!--EZCODE ITALIC START--><em>only</em><!--EZCODE ITALIC END--> Savage is just barely beveled in the bolt-head's rail slot.





This is also one of those topics that would be best discussed at a large round table with empty chairs inviting others, while being served ale by women with half exposed bosums. <!--EZCODE EMOTICON START :ms --><img src=http://x9eralpha.home.comcast.net/smile5.gif ALT=":ms">;





Take Care, Brad

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Niner
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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by Niner » Wed Jun 08, 2005 6:40 pm

Brad, I think you have a good idea there. :D;

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Re: No.4 Mk.I vs. Mk,I* bolt-heads

Post by T OHeir » Wed Jun 08, 2005 10:28 pm

"...I put a No.1 bolthead on my Mk.1*..." I'll bite. How? There's nothing for a No. 1 bolthead to connect to on a No. 4. I'd wager that you have bad headspace using the wrong bolthead.

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