devilfish13 6 Posted November 22, 2012 Report Share Posted November 22, 2012 One drill bit, three taps, what seems like a gallon of tapping fluid, three nights, and a lot of profanity later... I finally have my BG installed on my 7.62x39. I haven't test-fired it yet, but hand-cycling dummy rounds works great with both a Tapco and a milsurp... Others have warned about thicker metal and the job taking longer on a Vepr, I apparently didn't take it fully into consideration. I kept getting it tapped about 7/8 of the way and then it would stick... and I'd back it off, blow out the hole and clean the tap, more fluid, and... snap! First tap was the 2-flute from Dinzag, second one was a 3-flute from the local industrial supply shop... the one that finally made it all the way through? A cheap off-brand 3-flute TOOL STEEL (not HSS) from Menard's. It's all installed and looks quite pretty now, actually. I'm impressed. I suppose I didn't need to post about this, but after the frustration I guess I just wanted to vent. Anyone else have interesting experiences like this BG'ing a Vepr? Quote Link to post Share on other sites
adjc 171 Posted November 22, 2012 Report Share Posted November 22, 2012 (edited) One drill bit, three taps, what seems like a gallon of tapping fluid, three nights, and a lot of profanity later... I finally have my BG installed on my 7.62x39. I haven't test-fired it yet, but hand-cycling dummy rounds works great with both a Tapco and a milsurp... Others have warned about thicker metal and the job taking longer on a Vepr, I apparently didn't take it fully into consideration. I kept getting it tapped about 7/8 of the way and then it would stick... and I'd back it off, blow out the hole and clean the tap, more fluid, and... snap! First tap was the 2-flute from Dinzag, second one was a 3-flute from the local industrial supply shop... the one that finally made it all the way through? A cheap off-brand 3-flute TOOL STEEL (not HSS) from Menard's. It's all installed and looks quite pretty now, actually. I'm impressed. I suppose I didn't need to post about this, but after the frustration I guess I just wanted to vent. Anyone else have interesting experiences like this BG'ing a Vepr? i had issues with it also,done many saiga's and never had any problems. was more than 1/2 way thru on 7.62 vepr when the tap broke, went slow backed it out several times cleaned then snap! tried to shatter it out with a punch and a hard smack with a big hammer.....no luck. drilled the guide hole out a little bigger grabbed the mig and welded that bitch in. put two tacks in one on the front and one on the back of the guide.....2000+ rds later solid as a rock. did my homework with several builder's opinions on the trunion before putting heat on it and many said the metal was much more heat tolerate than the saiga being thicker and all....so it got welded. it's not going anywhere. Edited November 22, 2012 by adjc Quote Link to post Share on other sites
mikebaker1129 19 Posted November 27, 2012 Report Share Posted November 27, 2012 Hmm. I have tapped a couple of Saigas with out any issues. I have a New Vepr .223 and this has me concerned. I guess I need to look for a 3 fluted tap. I have the Dinzag taps and drill bits. Which size tap broke on you ? Quote Link to post Share on other sites
adjc 171 Posted November 27, 2012 Report Share Posted November 27, 2012 (edited) Hmm. I have tapped a couple of Saigas with out any issues. I have a New Vepr .223 and this has me concerned. I guess I need to look for a 3 fluted tap. I have the Dinzag taps and drill bits. Which size tap broke on you ? it was a 6/32 craftman's tap, was from an older set my dad had from many years ago. virgin tap never been used. Edited November 27, 2012 by adjc Quote Link to post Share on other sites
devilfish13 6 Posted November 27, 2012 Author Report Share Posted November 27, 2012 Hmm. I have tapped a couple of Saigas with out any issues. I have a New Vepr .223 and this has me concerned. I guess I need to look for a 3 fluted tap. I have the Dinzag taps and drill bits. Which size tap broke on you ? Mine were both 6-32, the 2-flute HSS from Dinzag and a 3-flute HSS from the local industrial supply shop. I was hesitant to use the 3-flute since I don't have access to a tap extractor with 3 fingers, only a 2-finger model at work. If I couldn't get it threaded with the cheapos I'd bought (I got 2 sets just in case), I was going to upsize it and use an 8-32, but didn't end up needing to. Btw, the guide works flawlessly and hasn't jammed on me yet over ~120 rounds split between fmj and sp from milsurp mags. Quote Link to post Share on other sites
mikebaker1129 19 Posted November 29, 2012 Report Share Posted November 29, 2012 Thanks for the intel ! Quote Link to post Share on other sites
thebuns1 4,323 Posted December 6, 2012 Report Share Posted December 6, 2012 Yeah these trunnions are a bit thicker. I went really slow and am suprised I didnt break mine on my 5.45. I had it squeaking but it never did break. I though it was going to though a few times. It took me almost 2 hours to get mine tapped. I dont use a tap wrench though. My method is rather hillbilly, as I use a pair of vise grips and bit down the tap a bit and lock it in the grips. seems to work great though, as Ive done several BG's now this way and havent had any break yet doing it this way. lol. Glad you got it in there though Squidkitten! Quote Link to post Share on other sites
draftpick 5 Posted December 6, 2012 Report Share Posted December 6, 2012 I broke 2 taps in my 7.62x39 vepr. Like the others I have done a couple saiga's and they were a brezze but the vepr was another story. Glad Im not the only one that had problems. Took about 2 hours to complete. Welding sounds like the way to go! Quote Link to post Share on other sites
mikebaker1129 19 Posted December 8, 2012 Report Share Posted December 8, 2012 I have been waiting on my BG to come in from Dinzag,and hearing that they were the same as the Saigas, I removed my Saiga BG and tapped my vepr for the BG and it was not too bad. It was not as easy as a Saiga, but it was not eo difficult. Quote Link to post Share on other sites
devilfish13 6 Posted December 9, 2012 Author Report Share Posted December 9, 2012 Yeah, they're the same. Sounds like you were either lucky or a lot more experienced with taps... I hadn't tapped anything in about five years, back when I was taking prereq's for CNC classwork. It ought to drop right in when you get it. Quote Link to post Share on other sites
mikebaker1129 19 Posted December 10, 2012 Report Share Posted December 10, 2012 I have tapped a few holes in my day, but I have had them break off before and they are a ***** to get out . I would say that I got lucky. I am going to help a friend drill and tap his next.He ordered his a couple days after I did. Are most of the taps breaking in the 7.62X39 models ? Quote Link to post Share on other sites
tbryanh 11 Posted April 29, 2014 Report Share Posted April 29, 2014 Has anybody ever riveted their bullet guide in with a rivet similar to the rivets used to rivet the receiver together? I think this way is mil spec and is probably the best way to do it. Quote Link to post Share on other sites
thebuns1 4,323 Posted May 25, 2014 Report Share Posted May 25, 2014 Ive seen a few people use pop rivets. They seem to have held up so far, but Ive never done one like the factory. Quote Link to post Share on other sites
tbryanh 11 Posted May 28, 2014 Report Share Posted May 28, 2014 I think the receiver is in the way for using a factory rivet. Quote Link to post Share on other sites
scattergun10 125 Posted June 11, 2014 Report Share Posted June 11, 2014 I just snapped a tap on my 5.45, SOB! So, what did you guys do to remove/extract the broken taps? Quote Link to post Share on other sites
Sdustin 578 Posted June 11, 2014 Report Share Posted June 11, 2014 (edited) You should be able to drill it out and tap larger. Our take a punch and chip it out. They are brittle. Edited June 11, 2014 by Ak Monty Quote Link to post Share on other sites
scattergun10 125 Posted June 11, 2014 Report Share Posted June 11, 2014 You should be able to drill it out and tap larger. Our take a punch and chip it out. They are brittle. Could I possibly drill it out with a smaller or same size bit? Then,pick up where I left off (so to speak) with a fresh 6/32 tap, so I don't have to go buy a bigger tap and screw? Quote Link to post Share on other sites
Sdustin 578 Posted June 11, 2014 Report Share Posted June 11, 2014 If try the punch first and try to break the tap into pieces. Quote Link to post Share on other sites
james lambert 3,059 Posted June 11, 2014 Report Share Posted June 11, 2014 You should be able to drill it out and tap larger. Our take a punch and chip it out. They are brittle. Could I possibly drill it out with a smaller or same size bit? Then,pick up where I left off (so to speak) with a fresh 6/32 tap, so I don't have to go buy a bigger tap and screw? You really cant drill taps, they are harder than most drills,. I have fractured them with tiny punches, but if its in very deep its a bear. you could try a tap extractor, but they have a habit of breaking as well, so go easy. In extreme cases taps have to be removed by plunge EDM PS you can also kill the temper of the tap with a torch, then it can be drilled Quote Link to post Share on other sites
nsnate02 32 Posted June 12, 2014 Report Share Posted June 12, 2014 I've done a bunch that went easy and then one that was PAIN. Broke two taps in it. First one, I was finally able to break out and the second one I was able to break out as well but it wasn't easy. I could only get about 1/2 a turn before they would bind. I think the drill bit was not the right size. Opened it up a bit larger and re-taped it and it worked fine. Quote Link to post Share on other sites
scattergun10 125 Posted June 12, 2014 Report Share Posted June 12, 2014 I've done a bunch that went easy and then one that was PAIN. Broke two taps in it. First one, I was finally able to break out and the second one I was able to break out as well but it wasn't easy. I could only get about 1/2 a turn before they would bind. I think the drill bit was not the right size. Opened it up a bit larger and re-taped it and it worked fine. What size did you eventually drill/tap it that worked? Quote Link to post Share on other sites
nsnate02 32 Posted June 12, 2014 Report Share Posted June 12, 2014 I've done a bunch that went easy and then one that was PAIN. Broke two taps in it. First one, I was finally able to break out and the second one I was able to break out as well but it wasn't easy. I could only get about 1/2 a turn before they would bind. I think the drill bit was not the right size. Opened it up a bit larger and re-taped it and it worked fine. What size did you eventually drill/tap it that worked? I think I went to 10/24 with a #25 bit IIRC. Mainly because that is what they had at the store. It was either that or 8/32 Quote Link to post Share on other sites
james lambert 3,059 Posted June 12, 2014 Report Share Posted June 12, 2014 Threads will develop most of their strength even in over sized holes. Its not uncommon to drill slightly over size holes to tap very hard materials. An 8-32 calls for a #29 drill (.136) A #28 is (.140) That would give you .002 per side, and make Tapping hard material a bit easier . If you happen to break a tap, It will extract easier as well. jim 1 Quote Link to post Share on other sites
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