Page 1 of 2 12 LastLast
Results 1 to 45 of 47

Thread: Honing .308 chamber for 7.62x51

  1. #1
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default Honing .308 chamber for 7.62x51

    I have a CAI R1A1 (FAL) chambered in .308 Win, a good pile of LC 7.62x51 GI brass and only a tiny bit of com. brass. With all my best efforts and SB dies the GI brass remains just a bit to large to fully chamber. Is flex honing the chamber a good idea? If so, should I use the #400 or #800 grit hone (only care to buy one) and would it be best to use the .308 or the 7.62x5 hone? Semper Fi.

  2. #2

    Default

    Best to send it to a gunsmith to see if there is a problem or buy a different brand of dies. I hate reloading LC!

  3. #3
    Join Date
    Dec 1969
    Location
    Crotch Of The Country
    Posts
    1,602

    Default

    If it were me, the chamber is the last thing I would touch. Try everything else first.

  4. #4
    Join Date
    Dec 1969
    Location
    Beach Va
    Posts
    8,248

    Default

    Quote Originally Posted by scottwilson View Post
    Best to send it to a gunsmith to see if there is a problem or buy a different brand of dies. !
    maybe a chamber cast and a custom die set?

    Quote Originally Posted by Shoots High View Post
    If it were me, the chamber is the last thing I would touch. Try everything else first.
    +1, have it checked to make sure it is in spec, ream only if it is not,,,
    what's so funny about peace love and understanding?

  5. #5
    Join Date
    Dec 1969
    Location
    Oldsmar, FL (Tampa Bay)
    Posts
    22,486

    Default

    The 7.62 brass is heavier so it has less capacity, and its headspace limits are a bit longer for full-auto use, but as far as chambering is concerned there is no difference between it and the .308.

    Make sure the brass is full length resized, all the way to the bottom, that you've set the die up properly, and that you've annealed the cases properly. The exterior dimensions of .308 and 7.62x51 cartridges are exactly the same so if the .308 works and the 7.62 doesn't than something is wrong with the brass, not the chamber, assuming its within spec limits. 7.62 service autoloaders are often chambered a bit bigger because a tight chamber can be a problem on a non-bolt action. An SB die is often resorted to on M14s and m1As when the quest for accuracy with a tight chamber causes feed and extraction problems.

    I suspect that you may not be running the die tight enough, or that the cases weren't annealed enough and the heavier brass is springing back. It can be tough to resize with a small base die
    I swear by Jupiter Optimus Maximus .... in the army of the consul Lucius Quinctius Cincinnatus and for 10 miles around it I will not steal anything worth more than a sestertius in any one day.

  6. #6
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    Interesting that no one has asked the most basic question of all - will it chamber a new cartridge?? If not, there is a problem in the chamber, not the ammunition. Don't even think about "honing" a chamber. Use a reamer, if necessary.

    If it will chamber a new cartridge, the problem lies in the brass. You simply are not sizing it enough. Try some other brass. If that doesn't work, borrow a set of dies, preferably small base, and try them.

    The LC cartridge is correctly called the 7.62MM NATO. There is no case length in the nomenclature. That is strictly European.

    Ray

  7. #7
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    Hint - If you determine that the problem lies in the brass, take one of your sized cases and completely paint it with a black magic marker. Then try to chamber it. When you extract it, it will show exactly where the problem is and you can concentrate your efforts on correcting that part of the sizing rather than chasing a problem that may not exist.

    Ray

  8. #8
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Mmmm. Maybe a little more background info is required here. Have been reloading since the early 60's and think I know how to screw a sizing die in (counter clockwise....right?). Before someone tells me to clean the chamber.......I spent 22+ years in the Marines and think I learned what a clean weapon looks like. I have 4 other rifles chambered in 7.62------this brass presents no problems in any of the other weapons save for one bolt gun that shows a little resistance when turning down the handle. The two auto loaders eat it up. Yes......fresh surplus ammo chambers just fine. If a empty sized case or a live reloaded round is chambered 2 or 3 times under force of the recoil spring, the round will then fully seat. I have found no marks on brass or bullet of these rounds that look like they came from anything other the slam-bam operation of the action . Thanks for the input to so far.

  9. #9
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    If a new cartridge chambers just fine but an empty sized case or reloaded round does not, there is something that is keeping them from chambering. You have to determine what that "something" is. It is certainly not the chamber. "Honing" or making the chamber bigger will probably allow you to chamber your reloads but that simply does not address the problem. A magic marker case has to show a sign of what is keeping the cartridge from chambering. You just need to look a little closer.

    If your reloads show a little resistance when closing the bolt of your other rifle, that tells you something. The case is too big. A properly sized cartridge should chamber with no resistence. Do the magic marker test on it and see where the problem is. It may be the same part of the case that is causing problems in the FAL.

    Good luck

    Ray
    Last edited by Ray Meketa; 08-16-2013 at 01:00 PM.

  10. #10
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    OK Ray, I painted up a live round with a MM, firing pin removed, and let the bolt fly home on it. The only marking on the round was at the junction of the case neck and case shoulder. It showed up a ring all the way around

  11. #11

    Default

    I don't reload so offer this suggestion in that light. You indicate that it's not seating properly. Could it be the necking? Is it possible that the neck is not allowing the body of the brass to go all the way in? You could lop off a neck from one of the cases and see if the case goes in correctly after that or try to use the marker idea. Strange as this sounds, when you've exhausted all other possibilities, what's left has to be the problem and it sure sounds like the brass is still not formed correctly to fit the chamber as opposed to when it was new.

    I bought my DPMS LR308b rifle just so I could burn through my surplus that I'd stashed over the years. When I got it, however, it was bored for .308win commercial (I wasn't offered a choice for some reason). However it handles my surplus just fine, thank you very much.

    Rome

  12. #12
    Join Date
    Dec 1969
    Location
    Beach Va
    Posts
    8,248

    Default

    Quote Originally Posted by 45to70 View Post
    OK Ray, I painted up a live round with a MM, firing pin removed, and let the bolt fly home on it. The only marking on the round was at the junction of the case neck and case shoulder. It showed up a ring all the way around
    Sounds like your die is not setting the shoulder back like it should..



    Sent from my DROIDX using Tapatalk 2
    what's so funny about peace love and understanding?

  13. #13
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    Quote Originally Posted by 45to70 View Post
    OK Ray, I painted up a live round with a MM, firing pin removed, and let the bolt fly home on it. The only marking on the round was at the junction of the case neck and case shoulder. It showed up a ring all the way around
    Now you know where the oversize problem is. It is not the base, so a SB sizing die will not solve anything. It is not an oversize body (or neck as Rome suggested). The neck/shoulder junction has to be pushed back just a tad. If you can't do that with your existing sizing die you may need to grind a little off the bottom. Then, by using the MM trick again, you can adjust the die to where it moves that junction back a little and just barely touches the shoulder so that headspace will not be affected.

    I'm a competition shooter and most other shooters that I know have custom dies that allow us to size any part of the case that needs it. We have base dies, body dies, shoulder bump dies, neck dies. Obviouisly, a factory FL die cannot be made to do these seperate operations but with a little adjustment (and maybe a modification) they can do a pretty good job of imitating the custom dies.

    Again, good luck.

  14. #14
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Ray, taking some off the bottom of the die sounds like a plan. I remember doing that about 35 years ago on a 357 seating die so could crimp 38's. Thanks.

  15. #15
    Join Date
    Dec 2008
    Posts
    2,259

    Default

    Just a thought, I've been following this but didn't post because I had nothing to offer untill the ranting & screaming stopped. But have you tried a different shell holder?

    I've seen a couple that were too thick above the rim where measurement isn't normally critical. Additionally its easier to face off a shell holder than remachine a die base. And yes I reload both commercial .308 & LC 7.62mm in a rifle like yours, a CAI Metric FAL.

    I've never actually needed a small base die & they are a pain unless they're really REALLY needed.
    When the entire world is PO'd at you maybe its you, not the whole world that has the problem!

  16. #16
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Another good idea, thanks.

  17. #17
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    Plonker - great suggestion.

  18. #18

    mad

    Maybe I missed it, but if the rifle came from CAI, then who knows which idiot build the darn thing. I'm guessing that the chamber needs to be recut to a military spec. That the non-military brass has just enough give in it to chamber, but if non reloaded rounds are working right then it must be a problem with the dies. I had a rifle that did the same thing, key word being had! I made it someones elses problem because I never count count 100% on it with whatever ammo it was fed.

  19. #19
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Well, I was thinking the same as Scott. As I understand it, Military chambers are cut a bit more generously and that's why I thought honing would be a solution. Getting the case a bit deeper in the die should fix the problem in the future, but will not help with the ammo have already loaded. Bought this rifle new 15-18 years ago-----test fired it with surplus ammo and put it in the rack where it sat until about two weeks ago.

  20. #20
    Join Date
    May 2010
    Posts
    237

    Default

    Might want to ask on the Fal Files. Swapping locking shoulders would be easier than reaming the chamber. If mine had this problem, I'd shave the shell holder or base of the die first like others recommended.
    As for the ammo you already loaded, send it to me for disposal.

  21. #21
    Join Date
    Dec 1969
    Location
    The Arizona Territory
    Posts
    8,098

    Default

    RCBS makes a Small-Base die set to address this issue. While I used primarily milsurp ammo in my R1A1, handloads sized with the small-base die worked flawlessly.

    It's good that you asked BEFORE taking abrasive to chamber, rather than asking for advice afterward.
    "Hey Look! We've got Guns ... and We've got Snacks!"
    - Cdr. Samuel "Sam" Axe, USN, (ret) -

  22. #22
    Join Date
    Oct 2012
    Location
    MN, USA
    Posts
    78

    Default

    I reload a lot of 30 cal and 308 (7.62) for MGs, AR-10, M1A and FALs. Do you have a case gauge? It sounds to me that the problem you have identified is that the brass has stretched and may need to be trimmed. Pushing the shoulder back will only aleviate some of the problem. the ring you are seeing on the loaded case shows the case is impacting on the actual throat of the chamber. The case gauge will allow you to determine OAL of the cases and determine if you are sizing correctly. These are available from a number of sources, and if you just want to check existing ammo and brass, I can send you mine on loan...... I just need it back in couple weeks.

  23. #23
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    MG08/15, thanks for the offer, but tried many remedies before posting here, overly long commercial brass chambered with no problems. Again, this brass and the reloads work fine in my other 7.62's..........but they are chambered for 7.62, not .308 like the FAL.

  24. #24
    Join Date
    Dec 1969
    Location
    Columbia, SC
    Posts
    1,161

    Default

    Headspace on a Fal is set with the locking shoulder, methinks you have the wrong one installed. A relatively cheap and easy fix.
    The Americans fight for a free world, the English mostly for honor and glory and medals, the French and Canadians decide too late that they have to participate. The Italians are too scared to fight; the Russians have no choice. The Germans for the Fatherland. The Boers? Those sons of bitches fight for the hell of it!” - American General, George “Guts and Glory” Patton

  25. #25
    Join Date
    Dec 1969
    Location
    Mo.
    Posts
    2,525

    Default

    Quote Originally Posted by hagar View Post
    Headspace on a Fal is set with the locking shoulder, methinks you have the wrong one installed. A relatively cheap and easy fix.
    I built a STG58 that I set the headspace a touch on the tight side and had the exact same problem. Change to a .001" (maybe .002") smaller locking shoulder and it eats resized everything. Headspaced with Forster go/no go gauges and it's 1.635" IIRC.
    Vigilance in Living counteracts Stupidity in Dying
    Per Scintillam Flamma

  26. #26
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    The rifle will accept new cases and new cartridges, so there is nothing wrong with the chamber or headspace.

    Your significant other is baking cookies but discovers that the cookie pan is too big for the oven. Some of you would suggest that he/she buy a new oven, or get out a hacksaw and cut away part of the oven door. I, (and others) are suggesting that you get a smaller cookie pan.

  27. #27
    Join Date
    Dec 2007
    Location
    New Iberia, Louisiana
    Posts
    1,415

    Default

    Just a suggestion here. Get two identical shell holders same brand and have someone either suface grind off .002 and .005 and see which one allows you to chamber your cases. I ran into a problem with a .308 and rather than cut the dies had two shellholders suface ground. They are hardened. Or lacking a shot at a surface grinder get a couple stones and measure the shell holders as you stone them. Frank

  28. #28

    Default

    45to70, I don't know why I didn't think of this before but I've got a complete set of Forstner gauges (go, no-go, field reject). I'd be happy to lend them to you to check your chamber before you attempt anything else. I've sent this set of gauges around the country a few times, allowing FAL and other .308/762x51 owners to check their respective chambers. These are arguably the best gauges you can get and my set was pulled from an order going to the military. In addition you don't have to pull your firing pin as there is a relief hole drilled into the base of the gauge. I can have them put in the mail to you tomorrow if you'd like. Just click on my avatar and you'll find my email address. Send me your address and I'll drop the gauges into the mail. Return them after you've check your chamber(s).

    Rome aka Cabinetman.

  29. #29
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Cabinetman, Sent two PM's but can find no record of them in my msg section so here goes, MSG follows: That is a very nice offer and would like to take you up on it. The gauges will of course end all the guess work. I will return them promptly along with your postage and insurance. My address is: Al Knapp, 3951 highway 1675, Somerset, KY 42501.
    Last edited by 45to70; 08-17-2013 at 11:24 AM. Reason: spelling

  30. #30
    Join Date
    Dec 1969
    Posts
    1,304

    Default

    If you have a problem with your chamber you need to use a chamber reamer to fix it. Using a hone will not give you a consistent change unless you are using a rigid hone. I have no idea what it would cost to do that sort of hone but I do know that its not going to be reasonable. Use of a ball hone or any other sort of drill type setup will just ruin your chamber. You need to be able to control how much you change it and after reading all the posts my guess is that the chamber is short or on the very short side of spec. The shoulder probable needs to be moved forward and for that you need a reamer, not a hone.
    Use the headspace guages and see where your shoulder is in reality and then go from there.

    Frank

  31. #31

    Default

    I got it. Both PMs got there. I'll have the gauges in the mail tomorrow so you'll be good to go knowing that your chamber is set. Use them on any other .308s you have, too.

    Let me know when you get 'em.

    Rome

  32. #32
    Join Date
    Dec 2008
    Posts
    2,259

    Default

    I hesitate to ask, but have you compared measurements from your resized cases, factory new unfired cases, once fired brass from your chamber & SAAMI specs?

    It might tell you which item (chamber, dies, or cases) is the root cause of your problem.
    When the entire world is PO'd at you maybe its you, not the whole world that has the problem!

  33. #33
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Plonker, Yes, that is one of the many things I did before posting, really could not find any difference. Some measurement are hard to take while trying to "hit" the exact same spots on the brass. In some cases the "no go" brass measured smaller in head. I think amafrank might be on to something with it being a very tight in spec chamber or Ray with my dies being bad. In any case Cabinetman's generous loan will tell the tail.

  34. #34

    Default

    Let me say here that anyone else who would like to try the three gauges in your rifles are welcome to do so. Once Al is finished with them he can send them to you before they head back to Connecticut. Just let him and me know here or via PM or directly email (my preference).

    Rome

  35. #35
    Join Date
    Sep 2010
    Location
    The Arizona Desert
    Posts
    1,860

    Default

    Quote Originally Posted by 45to70 View Post
    Plonker, Yes, that is one of the many things I did before posting, really could not find any difference. Some measurement are hard to take while trying to "hit" the exact same spots on the brass. In some cases the "no go" brass measured smaller in head. I think amafrank might be on to something with it being a very tight in spec chamber or Ray with my dies being bad. In any case Cabinetman's generous loan will tell the tail.
    Be sure to let us know here what you find out. I would love to know...

    grey
    If you think gun control is the answer, look what happened in Australia when they banned all hand guns in 1996? NEW LINK! 8/3/2013
    Try here -> https://www.youtube.com/watch?v=W4tS0DGDf0I
    or here -> https://www.youtube.com/watch?v=OyS3CEIbpJo

    English Warning "Our Gun Ban caused 40% jump in Gun Crime" https://www.youtube.com/watch?v=ZTyCD2n6HAQ


    A well regulated militia being necessary to the security of a free state, the right of the people to keep and bear arms shall not be infringed.

  36. #36
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Well, Got Cabinetman's gauges today. I believe that the chamber is on the tight side. With the weapon disassembled and using only modest hand force the gauge did chamber-----but with a little resistance (I engaged the rim under the extractor before testing). As stated earlier a fresh surplus round will chamber ok-------but I believe that new ammo is all under max dimension and would give a small margin of grace. Ideas???????????

  37. #37
    Join Date
    Dec 2008
    Posts
    2,259

    Default

    Off the wall suggestions.
    1. Change your lube. Maybe the lube is not slick enough & is allowing the case to spring back a tad too much after resizing. Try Imperial maybe lots swear by the stuff.
    2. Polish your expander ball highly & use a dry lube in the case neck inside. Thats supposed to reduce case stretch & so on when bringing the sized case back down fror resizing.

    I know, they're a bit nutty but worth a try.
    When the entire world is PO'd at you maybe its you, not the whole world that has the problem!

  38. #38
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Thanks plonker will give it a try, do think the expander ball could use some cleaning up. Think the problem is a tight chamber and loose sizing die------might have never had a problem if it was just one of the two. Will also "shave" the sizing die down a bit. Filing down the shell holder is a very good idea but am using a progressive press so will work the die instead. Thanks for all the help.

  39. #39
    Join Date
    Dec 1969
    Posts
    6,964

    Default

    I'm not a reloader but I believe that the FAL does prefer a little more headspace than most US users like to see. My FFL reloads for his but complains of issues once the gun gets warm. It could be he is using the wrong powder, but I also think his has tight headspace. Put it like this, if a FAL closes on a .308 No-Go but not a .308 Field, I would not sweat it at all. Others would be wailing and stamping their feet. NOTE: I said .308 gauges NOT 7.62 NATO.
    Damn the expense, use your turn signals today... and as a special favour, try doing it before you have two wheels in the next lane.

  40. #40
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    Well, well, well. Took .001 off the bottom of the sizing die and went to polish the ball expander. Decided to measure it for kicks, first reading was .307 (that's about right) and rotated it 90 degrees and came up with .311, just on the leading edge, the rest of it was fine (lee type). Ground the offending leading edge down and polished the whole thing. Did not see any deformation on the expander, think it has always been that way and my other rifles just did not notice. This FAL does have a tight chamber as witnessed by Cabinetman's gauges. Ran the re-resized brass through the rifle and all is sunshine and lollipops. Thanks to all.

  41. #41
    Join Date
    Dec 1969
    Posts
    1,304

    Default

    Remember to keep ammo loaded for this particular rifle separate if you have other .308's. If you set the shoulder back it will affect headspace in other guns and if you go over by too much you can have case head separations in those guns. That may be a "no big deal" thing or it can be catastrophic. If you have other rifles which headspace on the go but not the no-go you should be fine but any that allow the no-go may be bad with shortened ammo. Remember also that we don't always control our own destiny and if you wife or family dispose of your estate someone else may be the recipient of ammo that is unsafe. Our acts can have consequences way down the line......In other words here, mark the boxes you keep the ammo in to let yourself and others know that shoulder has been bumped back shorter than normal. If this were my rifle I would be more likely to fix the chamber than the ammo. It saves a lot of time and problems with fiddling around on dies and shell holders and means you can shoot normal ammo, not specially prepared ammo that could damage another gun.

    Hope some of this makes sense and helps.

    Frank

  42. #42
    Join Date
    Dec 2008
    Posts
    2,259

    Default

    I wonder if the neck is tight not the whole chamber? Egg shaped necks might be a problem!
    When the entire world is PO'd at you maybe its you, not the whole world that has the problem!

  43. #43
    Join Date
    Oct 2009
    Location
    Higher AZ Mountains
    Posts
    1,357

    Default

    45to70

    So, you took .001" off the bottom of the FL die, sized the cases, and now they fit OK? Did you happen to check with a Magic Marker to see exactly what part of the case was changed? .001" seems like an awfully small correction.

    plonker - an egg shaped neck is going to be round shaped after the bullet is seated.

    Ray

  44. #44
    Join Date
    May 2010
    Location
    ky
    Posts
    33

    Default

    I think the expander ball was the problem all along. It may have been pulling the shoulder forward as the case was extracted from the die. Did not do a MM test but think the extra .001 is a good idea with a chamber that runs on the tight side.

  45. #45
    Join Date
    Dec 1969
    Location
    Columbia, SC
    Posts
    1,161

    Default

    I had that problem with both 243's I owned, that expander would stretch the neck on the backstroke. I fixed that by sizing them with expander ball in place, and then ran them through again without expander. The 243 was the most pain in the rear cartridge I ever loaded for..
    The Americans fight for a free world, the English mostly for honor and glory and medals, the French and Canadians decide too late that they have to participate. The Italians are too scared to fight; the Russians have no choice. The Germans for the Fatherland. The Boers? Those sons of bitches fight for the hell of it!” - American General, George “Guts and Glory” Patton

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •