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Can someone enlighten me to the difference in bolt head lengths of these two actions. I am a little confused. I know the Mex is a shorter action overall,but, apart from that: Does the shorter bolt head of the Mex. mean that the reciever has less metal behind the lugs? Are the boltlugs themselves the same dimensions as a STd.98? So from my understanding the Mex is: a shorter action, has shorter front ring and, a shorter bolt head.....??? | ||
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the mexican mauser is shorter between the action screws, which means the bolt is shorter in more of less the same area. it is a SMALL RING action, and the changes are all in the bolt body, everything else is the same jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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The difference between a Mexican SR 98 bolt and an intermediate bolt is twofold. The biggest difference is the Mexican requires a unique extaractor due to the shorter distance between the extractor groove and the bolt face. I haven't studied it that closely but I would imagine it is this shorter distance that contributes to the overall shorter length of the Mexican bolt compared to the intermediate. If you put an intermediate bolt in a SR Mexican action the bolt face will protrude through the "C" ring.  Aut vincere aut mori | |||
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z1r, to restate, I was answering between mexican mauser and a m1898. Not to be overly corrective, but with you put anothe rintermediate bolt in a mexican 10 or 36 action, the shroud stands off about .085 or so of the rear of the action. You can then headspace normally on a new barrel/chamber and works perfectly.. jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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Jeffe, I was speaking to the unasked question of the differences between the Mexican bolts and the intermediates which many think are interchangable. While they are roughly the same length I was illustrating the differences which I'll elaborate further on below. Sorry, but the bolt face on an unaltered intermediate bolt protrudes roughly 0.025" beyond the inner "C" ring of the Mexican 1910 action. A 1909 bolt measured .023" and an M48 measured .025". I'm not going to disassemble my 1936 to measure it. The guide nubs on either side of the ejector slot in the upper bolt lug protrude even further. Mine measured .097". That would be on an intermediate bolt so equiped. The M48 bolts are lacking these guides so there the only concerns would be the boltface & extractor projecting past the inner torque shoulder. It would be possible to rebarrel and use an intermediate bolt but not without first counterboring the breech. Aut vincere aut mori | |||
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Z1R, thanks for clearing that up. Though using turk bolts in mexican mausers has been aroudn along time. When sarco? century? had those hundreds of mexican receivers, lots of guys built them on mexicans. I had one in 257 roberts, nothing to write home about, but it worked. If i take a properly fitted 1936 (one in 708 and one in 376), I can take the bolts out, take a turk bolt, and close the action. I am suggesting that the .025" protrusion into the C ring is immaterial in building a rifle, as that area, in regards to cases is nominally unsupported/unenclosing, and that additional .025 COULD make a difference, but practically shouldnt. Did I just confuse myself on that? In any event, just behind the rear bridge, as the third lug also lines up, the gap between action and shroud is larger using a turk bolt, but not a HUGE about, as the diff in a mexican and turk bolt seems to be behind the third lug. Mexican mausers (SRs) were my second "habit" after springfields, so i've built a couple on both action... some even turned out right!!! jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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jeffe, The bolt face protrudes BEYOND the "C" ring not just into it. Into it would just do as you say and support more of the casehead. But protrusion beyond the C ring won't allow the barrel (breech) to seat against the "C" ring unless you counterbore the breech. Aut vincere aut mori | |||
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Cool.. we'll agree to disagree.. and i'll take a pic or three to clear that up, if that's good with you? jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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I don't want to get into this argument,but...... I have several Mexican 1910 actions and a bushel of Turk 1903 actions. When you insert a Turk bolt into a Mex. action, the bolt nose protrudes beyond the inner "C" ring approximately 1/8". Unless a counterbore is cut into the breech end of the barrel, the barrel could not be tightened against the "C" ring. I guess you could just tighten barrel against the receiver face and leave a gap at the breech end to allow for the protruding bolt nose, but, that's not something that I would want to do. Rojelio | |||
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Thanks Rojelio for the confirmation. Jeffe, No less an expert than Jim Wisner has explained this to you before: https://forums.accuratereloading.com/eve/forums/a/tp.../750107381#750107381 Aut vincere aut mori | |||
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z1r, Hey, on a blue collar guy’s hunting rifle does it really make a difference?  | |||
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Yes, JIm posted that there are differences.. and I ahve the parts on hand, so I'll go over to the shop either tonight or tomorrow and take a look. I have zero problem saying I am wrong.. yet, same as everyone else, when i think I am right, I tend to stay the course. I'll post finding either tonight (have clas tonight) or tomorrow night am I being stubborn? Could be. Don't mean to be rude, but I wouldn't mind actually sticking 2 pieces together. Zlr, like the majority of posters on here, you have a ton of expereince. I respect that you do. Let me take a look and prove myself wrong, k? jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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Jeffe, Sometimes it is best to prove things yourself. I'd have posted a pic last night but the wife took the camera with her when she went to Denver. Here is another where Jim Wisner says how the intermediate bolt can be made to work with mods. https://forums.accuratereloading.com/eve/forums/a/tp.../298104443#298104443 -Mike Aut vincere aut mori | |||
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Z1R, sure looks like you are correct!! I'll still take a pic!   opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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Jeffe, The only reason I know is because it wasn't til my fourth Mexican action that I got one with the right bolt. I spent a long time looking for ways to make it work but patience paid off in the end and between just plain dumb luck and good friends looking out for me I managed to scrounge up all the right pieces. The pics will be helpful to all I'm sure.  Aut vincere aut mori | |||
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well damn, i am totally wrong.. the turk bolt I got with the action was already turned down... the one I jerked out of an action NO GO jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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