Glk21C Posted July 22, 2011 Share Posted July 22, 2011 For those that own either or both of these mags in the topic title, I need your help. I know the new K40 mags have a thin spacer in the back, the K10's don't. However, due to ribs down the sides of the K10's, there appears to be a capacity issue (bulging of the sides) when more than 15 rounds are loaded. Also, the front shape where the mag catch hole is on the K10 appears to be different than the old style, so they might be prone to falling out? I run a long OAL load in my Limited (1.175 OAL) as compared to factory .40 length. Can someone who owns a K40, with some longer rounds, tell me for sure, yes or no, that a round of that length will feed reliably?? I've already got four other old-style .40 (non-spacer) and 10mm mags that get 20+1 or 21+1, so having one mag with a little less capacity is OK, but I'd rather have closer to 20 rounds available than 15 rounds available. Just want to make the right decision on which mag to get, the K10 or K40. (If I didn't have over 2000 rounds already loaded to 1.175, I'd would just get the K40...) Much thanks in advance for anyone's help Link to comment Share on other sites More sharing options...
Skydiver Posted July 22, 2011 Share Posted July 22, 2011 I'm guessing you missed this thread: http://www.brianenos.com/forums/index.php?showtopic=127917&view=findpost&p=1493234 Link to comment Share on other sites More sharing options...
Glk21C Posted July 23, 2011 Author Share Posted July 23, 2011 Thanks, I did read that one. James seemed indicate, to me, that he was loading to an OAL of 1.125. I realize he did measure the inside of the mag when I wrote my question, so in theory the 1.175 OAL round should feed if the internal dimension is 1.185. But has anyone run an OAL of about was I was asking in the K40 and have it feed with no problems? Thanks Link to comment Share on other sites More sharing options...
Nealio Posted July 23, 2011 Share Posted July 23, 2011 Do you need your OAL that long? Do you load long for feeding our for pressure? Link to comment Share on other sites More sharing options...
Glk21C Posted July 23, 2011 Author Share Posted July 23, 2011 I've always loaded that long, for both the reasons you mention, plus makes it softer to shoot. Again, if I didn't have over 2000 rounds already loaded, I really wouldn't be concerned Link to comment Share on other sites More sharing options...
Nuke531 Posted July 25, 2011 Share Posted July 25, 2011 I got one of the K40 mags when I bought a new .40 top end for my Stock 1. I load my .40 out to 1.182 and my load will not fit in the mag I got, If that helps any. I loaded up some 357 sig into it just to see if it would load and it worked well. This is odd because I cant load 357 sig into my old Tanfoglio mags with out them binding up after the 4th or 5th round. If anyone is wondering why Im going to be getting a Tanfoglio in .38 super and I would like to convert to 357 sig. Link to comment Share on other sites More sharing options...
Nealio Posted July 25, 2011 Share Posted July 25, 2011 I got one of the K40 mags when I bought a new .40 top end for my Stock 1. I load my .40 out to 1.182 and my load will not fit in the mag I got, If that helps any. I loaded up some 357 sig into it just to see if it would load and it worked well. This is odd because I cant load 357 sig into my old Tanfoglio mags with out them binding up after the 4th or 5th round. If anyone is wondering why Im going to be getting a Tanfoglio in .38 super and I would like to convert to 357 sig. Why not a 9x25 Dillon?? Link to comment Share on other sites More sharing options...
Casman Posted July 26, 2011 Share Posted July 26, 2011 Hey Artie, Sorry, I just saw your PM and thought I would reply here. The short answer is that no, I don't know if 1.175 will run in these mags. The longer answer is that I am loading tonight to do some more testing tomorrow and will load some up at that length and post here about it when I know. I totally understand the reluctance to change load length when you are already invested in mags and many rounds loaded. I started off this direction now because I was at a good point to make the change and I really wanted to be sure that if the old style 10mm mags became impossible to get we still had good options. The other major driver for me was to see if the new mags would give us Tanfo shooters the flexibility to pick up a box of shells at Wal-Mart if the need arose. At this point in time, I am pretty comfortable saying that all of these questions have been answered, for me, in the positive. I am really beginning to like the new loads, except the cost of N320, and everything is running smooth as can be. I'll let you know tomorrow what I find out about the 1.175 OAL. James Link to comment Share on other sites More sharing options...
Glk21C Posted July 26, 2011 Author Share Posted July 26, 2011 Much thanks, that is the kind of info I was hoping for. Link to comment Share on other sites More sharing options...
Casman Posted July 26, 2011 Share Posted July 26, 2011 (edited) Ok, so here is a bit of an update post loading. I started with 1.175 and worked my way down until I got a full mag to run without rounds camming and jamming. I ended up at 1.145" but I would not recommend this length as there was notable drag on the rounds still. If you want to stretch the round out in the new mags I would recommend using 1.14 as the max length. This does actually jive with the info I have on the old mags as well. To my knowledge the longest anyone is loading for the old mags is 1.25" which gives 0.045" of play. If you take the internal dimensions of the new mag and subtract the same clearance you end up at 1.14". Remember that the rounds are not always perpendicular to the diameter of the mag tube, the diagonal measure of the round has to be able to clear or you will get a round camming inside the tube and the maraca effect. I'll shoot the 1.145" OAL rounds I loaded tomorrow and let you know how it goes. Personally, I am inclined to stay at 1.125", they are running beautifully, feel great and mimic factory rounds so load development is a bit less of a guessing game. Oh yah, the load I am currently using for the 1.125" load is 0.4 grains below max to make major. I havent been in that territory for years; it kind of gives me a warm fuzzy feeling. Have a good one. James Edited July 26, 2011 by Casman Link to comment Share on other sites More sharing options...
Skydiver Posted July 26, 2011 Share Posted July 26, 2011 Knowing 1.125" is mostly useful, but it would also help it you tell us what bullet and bullet profile you are using. Are you using hollow points, round nose, truncated cone, semi-wadcutter. etc. What bullet manufacturer: Montana Gold, Berry's, Delta Precision, Rainier? This may help us readers a bit more to visualize where the possible jam/rub points are when the bullets go down into the mag and work their way back up again. Any which way, thank you for posting what you are learning! You are helping the community dramatically. Link to comment Share on other sites More sharing options...
Skydiver Posted July 26, 2011 Share Posted July 26, 2011 I broke open my reloading manuals because I'd not loaded any standard length .40 S&W. I'd gone straight to loading long. Apparently SAAMI spec OAL for .40 S&W is 1.135". So in theory, the mag should support bullets out to 1.135". Link to comment Share on other sites More sharing options...
Casman Posted July 26, 2011 Share Posted July 26, 2011 I broke open my reloading manuals because I'd not loaded any standard length .40 S&W. I'd gone straight to loading long. Apparently SAAMI spec OAL for .40 S&W is 1.135". So in theory, the mag should support bullets out to 1.135". True enough on both points. The bullets I have tested so far are TC-FMJ and JHP. Manufacture of the bullets is Zero. I can't say that I have noticed any difference in function between the two profiles. Initially I tested a bunch of Blazer, Remington, and Federal factory rounds as well. Today I will be testing RNFP- plated bullets by Extreme. As for the SAAMI OAL, I used the most current published load data from the powder manufactures I was testing. Those lengths were 1.125 and 1.126, which also matched what I got when I measured the factory rounds. Based on my little length trial last night I would have not worries about running 1.135" in these mags though. That will still give you a good buffer space in the mag for whatever bullet profile you prefer. James Link to comment Share on other sites More sharing options...
Casman Posted July 27, 2011 Share Posted July 27, 2011 Ok, so I have Good News and Good News. Which do you want first? From least to greatest... The 1.145" rounds all ran just great; no hang-ups at all. Predictably, they were a tad slower with the same powder drop as the 1.125" rounds and the ES was a bit greater but not terrible. The much bigger good news is that we do have fully capable, functional, reloadable, 21+1 mags. I met Henning out at the range this afternoon and was filling him in on what I had observed so far. (It is worth noting that I have been mostly shooting new brass; don't ask bad planning on my part and I have been out of good resized brass.) As I was in the process of telling him the 20+1 worked great but that 21+1 was probably going to be difficult he was loading a mag, with freshly roll sized brass. As soon as I finished telling him about the load numbers he looked over and said, "I think I just loaded 21." He unloaded the mag on the table and sure enough 21! We tested all the mags I have and they all now take 21+1. The only notable difference is that the older base pads, that are a bit shorter, would be a tough reload; they work fine once seated but are tough to seat. The newer base pads will take 21 and reload easily. It seems that a combination to mag spring break-in and the rolled brass is enough to make it work. New brass is still very hard to get 21 loaded but roll or push through brass seems to work just great. On top of that I didn't have a single problem with the slide short stroking because of too much pressure from below. I hope that this info helps. I have been a confirmed Tanfo shooter for a few years now and this all just makes me grin ear to ear! James Link to comment Share on other sites More sharing options...
Laid Back Posted August 3, 2011 Share Posted August 3, 2011 (edited) Ok, got the new mags from Henning that have the Grams follower and are supposed to hold 18. When I load the mag to capacity, the follower gets stuck at the bottom of the mag. This happens to all of them, it's not just one. Also, when trying to load the first round, the rear of the follower won't depress if I put pressure on the front of the follower, therefore I have to use my Uplula to load the first round. Is this normal? Nevermind, problem solved. Thanks Henning. Edited August 5, 2011 by Laid Back Link to comment Share on other sites More sharing options...
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