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polish and teflon coat the feed ramp on an M70?
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Well let me tell ya, I am gonna singlehandedly help my smith get some excellent 1st quarter earnings. I now have 3 rifles to drop off sometime in the near future.

So, I got my nice shiny new Williams extractor for my 7mm, installed it in 2 sceonds flat, easy as cake. So, I get out some FL sized ammo to make sure everything is working alright. I pop one in the mag, and cycle the bolt at a moderate pace, slowing up @ the end. Did not want a repeat of 2 weeks ago killpc

So anyways, it starts to get stuck AGAIN. But I get the round out, and the brass is scored down the length from the top of the feed ramp! I had pondered for a sec that this is what happened 2 weeks ago, but I remebered I was able to close the bolt. Now the round was jamming slightly from the base not sliding into place on the boltface, and the top of the feed ramp gripping the brass from the rough finish. I was able to chamber rounds only if I cycled the bolt with authority and speed.

Yes, I know, you are supposed to cycle the bolt quick and firm for a follow up shot, but the scratched brass really freaks me out. I want rounds to chamber like BUTTAH!

Now, I definately figure I need the smith to do some polishing(or maybe Chuck Norris can rub his beard on it), but would you get the feed ramp coated with some form of teflon, NP3, or Roguard? Or just get it reblued?

Would polishing the boltface help the cart slide into place better also?

Thanks for the help. I still owe you guys beers for helping with the Sako extractor. beer
 
Posts: 986 | Location: Columbia, SC | Registered: 22 January 2005Reply With Quote
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I would just polish it and not worry about any coating. If you reblue you would need to do the entire barreled action cold plue would wear off quickly. For Teflon etc to stick you need to bead blast it. Defeats the purpose of polishing. Often the edge of the chamber will cause a scratch and needs to be polished or chamfered.

If the rifle is CRF M70 a smooth bolt face might help. ON a push feed I don't see how it would help.


As usual just my $.02
Paul K
 
Posts: 12881 | Location: Mexico, MO | Registered: 02 April 2001Reply With Quote
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Well, I had a problem with my M70 270WSM feeding the last cartridge in the mag - it was not feeding up all the way onto the bolt face. Turns out the extractor had so much tension on it, that the rim of the case got stuck before it would get all the way up onto the bolt face. I found several threads about this on www.shortmags.com or .org, ?, . . . Anyway, someone suggested taking some of the tension out of the extractor by slightly bending the rear part of the extractor out. It tried this, using a flathead screwdriver (with a shop towel over it to keep from scratching the bolt) for a lever. Took 5 or 6 tries, slighter more force each time, until it worked. Now, the extractor has enough tension to hold the cartridge, but not enought to prevent the rounds from feeding up onto the bolt face properly.


We Band of 45-70er's
 
Posts: 178 | Location: Pearland, TX | Registered: 15 January 2003Reply With Quote
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First your feed ramp should be polished to a pretty fine grit and left without any coatings.

Second these aftermarket extractors need to be hand fit to each action, despite what the manufacturers tell you. They need the proper tension, which is what TXRam is referring to. I'm not sure about his method though. I'm at a lose as to how these extractors will achieve proper tension on a one size fits all mentality. Don't get me wrong they are wonderful additions and done very well, but they need to be fit.
 
Posts: 210 | Location: NW Wyoming | Registered: 20 February 2003Reply With Quote
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What would be the proper method? This is a sincere question, please don't take it any other way. Thanks, Clint


We Band of 45-70er's
 
Posts: 178 | Location: Pearland, TX | Registered: 15 January 2003Reply With Quote
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TXRam,

Shaping the extractor, filing, polishing, etc. Don't get me wrong I'm not an expert at it. These methods would seem to reduce tension so maybe bending works for adding tension. It is also a good idea to measure the tension with calipers. The rifle builder I worked for had an ideal tension he liked to see.
 
Posts: 210 | Location: NW Wyoming | Registered: 20 February 2003Reply With Quote
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funny wou should mention shaping the extractor blade. After doing some work with the 600 grit wet/dry and WD40, I got the machine marks off of the bolt face. I then tried to chamber the dummies, and I can see the reason why my brass is gettin marked up. First off, its not the feed ramp cause the binding starts @ the last 3/4" of bolt closure. The round is scraping the bottom of the chamber hard to get the round to seat all the wayup on the boltface against extractor tension. Right before the brass disappears, you can see the rim snap up into place.
 
Posts: 986 | Location: Columbia, SC | Registered: 22 January 2005Reply With Quote
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