dbletap_ed Posted June 14, 2015 Share Posted June 14, 2015 I have a good quantity of .224 SMK 77gr bullets which I did not have great luck with in my JP rifle. The groups were not bad but not as good as SMK 69gr bullets. Since I have the 77's I thought why not try loading them longer than mag length to see what happens. (Yes, I know I will have to single load them) The question is what is a good starting point for how far off of the lands to start? Note I will use a Sinclair Bullet Seating Depth Tool to find the OAL for the bullet touching the lands. Thanks Ed Link to comment Share on other sites More sharing options...
Steve RA Posted June 14, 2015 Share Posted June 14, 2015 Try .005 and if that doesn't work, make them shorter by the same .005. After doing that two or three times you should have hit a sweet spot. Link to comment Share on other sites More sharing options...
johnsons1480 Posted June 14, 2015 Share Posted June 14, 2015 With bolt rifles I've always loaded to a known safe powder charge far below max. Then I seat 5 bullets each as follows. .020 from the lands, .015 from the lands, .010 from the lands, .050 from the lands, touching the lands, .050 into the lands, .010 into the lands, .015 into the lands, .020 into the lands. Once you have the seating depth that works best for that bullet, THEN you work up your powder charge and find the most accurate load without pressure signs based on that seating depth. Link to comment Share on other sites More sharing options...
LikesToShoot Posted June 18, 2015 Share Posted June 18, 2015 Ed, I'm going to be playing with loading off the lands shortly but will be using some borrowed tools to get measurements off the ogive. This video was helpful, when it's not bogged down, Here's another one showing how bullet lengths can vary greatly and explain why COL can be so different using the same bullet. For sure I won't be loading down into the lands with my AR. Once, while shooting bench rest, they had to call a cease fire during the match and when the guy next to me pulled his cartridge the bullet was stuck in the barrel with powder all over the place. That guy then too had a problem that needed to be corrected. I'd be interested in how far off the lands works with those 77gr. Link to comment Share on other sites More sharing options...
dauntedfuture Posted June 25, 2015 Share Posted June 25, 2015 It does not matter with a 77. If were talking a VLD bullet then yes. Just like a 168 or 175 in .30, 77's jump just fine and you dont gain anything by seathing them close. Link to comment Share on other sites More sharing options...
dbletap_ed Posted June 25, 2015 Author Share Posted June 25, 2015 OK I thought the SMK 77gr bullets qualified as VLD's. Link to comment Share on other sites More sharing options...
Corey Posted June 25, 2015 Share Posted June 25, 2015 You might see some improvements with a change in seating depth but it wont be drastic like a VLD style bullet from Berger for example. Link to comment Share on other sites More sharing options...
dauntedfuture Posted July 1, 2015 Share Posted July 1, 2015 A 77 SMK is not even close to a VLD bullet. It has a relatively high BC but its not a VLD bullet. On a similar line I have loaded and shot some 77 TMKs and you have to seat them deeper in the case and they jump and shoot just fine. Link to comment Share on other sites More sharing options...
dbletap_ed Posted August 8, 2015 Author Share Posted August 8, 2015 I finally loaded up two loads with the 77 SMK's 0.01 and 0.02 off of the lands. The load 0.01 off of grouped at 0.6" and the 0.02 off of the lands grouped at 0.75". Both are much better than the 77's loaded at mag length. However, at best only as good as the 69 SMK's at mag length on an average day. Link to comment Share on other sites More sharing options...
bushmeat Posted August 11, 2015 Share Posted August 11, 2015 I loaded 77 TMKs to 2.482 OAL. Shot 5 rounds touching, 0,4" at 100. Before this, none of my 77 loads shot tighter than 69 SMKs. Link to comment Share on other sites More sharing options...
RDA Posted August 11, 2015 Share Posted August 11, 2015 I loaded 77 TMKs to 2.482 OAL. Shot 5 rounds touching, 0,4" at 100. Before this, none of my 77 loads shot tighter than 69 SMKs. Exactly what caliber and what type of gun are you able to use 2.482" OAL? Link to comment Share on other sites More sharing options...
bushmeat Posted August 12, 2015 Share Posted August 12, 2015 5.56 AR. Isn't that what this thread's about? Link to comment Share on other sites More sharing options...
RDA Posted August 12, 2015 Share Posted August 12, 2015 5.56 AR. Isn't that what this thread's about? I thought so until you posted that you loaded "77 TMKs to 2.482 OAL", I have never heard of any 77g bullets loaded to 2.482 in .223/5.56. I have heard of 80g bullets loaded this long and fed individually/manually as they won't fit in the magazine. Link to comment Share on other sites More sharing options...
bushmeat Posted August 12, 2015 Share Posted August 12, 2015 If you reread the OP, he was talking about loading 77s longer than mag length. The TMKs just came out a few months ago. Wait a bit. Others will start loading them long too. Link to comment Share on other sites More sharing options...
RDA Posted August 13, 2015 Share Posted August 13, 2015 If you reread the OP, he was talking about loading 77s longer than mag length. The TMKs just came out a few months ago. Wait a bit. Others will start loading them long too. Apparently, reading is still fundamental, I completely overlooked the sentence wanting to load longer than mag length by the OP. My apologies and carry on. Link to comment Share on other sites More sharing options...
dbletap_ed Posted August 14, 2015 Author Share Posted August 14, 2015 Bushmeat just wondering what barrel you are using. I had not given my OAL but it was 2.373 to be off of the lands 0.01 in my JP barrel. Again with SMK's not the new TMK's. Link to comment Share on other sites More sharing options...
bushmeat Posted August 15, 2015 Share Posted August 15, 2015 Bushmeat just wondering what barrel you are using. I had not given my OAL but it was 2.373 to be off of the lands 0.01 in my JP barrel. Again with SMK's not the new TMK's. My SPR is a 5.56 which has a longer throat than .223 or Wylde. Also bear in mind the TMK is slightly longer with a different ogive. The base is in about mid-shoulder and I get 2800 fps wth just a slightly flat primer and no marks. Link to comment Share on other sites More sharing options...
dauntedfuture Posted September 9, 2015 Share Posted September 9, 2015 I have shot some of the 77 TMKs loaded to mag length. The BC of this bullet is about .420 which is the same as the sierra 80. Provided you are going to load long then you are better off looking at another bullet like the sierra 80 or some of the other real slick bullets like the Bergers or the JLKs. The advantage the 77 TMK provides is that you can load a .420 BC bullet to magazine length. I suspect that loading a 77 TMK long will yeild little real advantage over a mag length bullet under an objective 10 round test. You will be able to fit more powder in the case and get slightly higher velocity. This bullet was designed for mag length, load and shoot them that way and be happy. So far they have shot well in several rifles and all i did was swap out bullets. Link to comment Share on other sites More sharing options...
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