SMK 150 Grain 6.5 CM January 08, 2019, 09:08:22 AM Has anyone been reloading with the new SMK 150's? I was out the other day with my first attempts with them, and had decent SD's and velocities starting at 42 grains of superformance with .5 grain increments up to 44 Grains which got me to 2790FPS with an SD of 11. I plan on going up to 45 grains, but my groups were awful at 100. It could have been me, the wind, and the fact that my battery on my magneto was about to die. I was rushing. Thoughts/Help will be well received.Thanks.
Re: SMK 150 Grain 6.5 CM Reply #1 – January 08, 2019, 09:43:00 AM IMO you are trying to push it too hard in the Creedmoor case. Try to find a load that will get you in the 2690-2720 fps range with them seated at 0.010" off of just touching the lands. I've only shot the 150 SMK's in a case with about 9-10gr more capacity than the Creedmoor case and although I could get stellar groups up to 300yds, at 600 and 1000yds I was getting some 'out of group' shots that cost me in competition. However, I need definite .5MOA precision over 20+ shots for my needs and I strive for .3MOA over 5-8 shots in testing loads at 300yds. The 150 SMK's could not consistently give me that.
Re: SMK 150 Grain 6.5 CM Reply #2 – January 08, 2019, 10:50:08 AM Exbonesny......What's your twist rate ?? I would guess the pill is not fully stabilized at 100, at those speeds, and with an 8 twist barrel. I'm gearing up to work with this bullet. As a matter of fact,Fedex is due today to deliver my 500 lot. I'll try to post a picof the length differences between the 140 RDF's, 142 SMKsand the 150 SMKs.....Sierra does say for the Creedmoor loaddata, you need a 7.5 twist or faster. I have a 29" , 7.5 twist barrel coming from Brux. As Rardoin mentioned about capacity,my plan is to load out long, in a single shot action, and startthe work with R-23.....Right now, I'm just a squirrel gatheringnuts. May not see any real data till April. Last Edit: January 08, 2019, 10:54:02 AM by Fuj
Re: SMK 150 Grain 6.5 CM Reply #3 – January 08, 2019, 10:52:55 AM I tried from 44.3 to 47 Superformance on those pills, in my SAV 10 24" 8:1, and got 2670 to 2860 fps.Best groups were at 44.3, but it seemed to be on the ragged edge of stability and those groups were unacceptable (+1.5 MOA).Stopped working with the 150 SMK cause apparently my 8:1 twist is not fast enough.
Re: SMK 150 Grain 6.5 CM Reply #4 – January 08, 2019, 12:39:07 PM That bullet is fully stabilized, with his info.2790 fps, 8 twist, (60 degs temp.) (500 feet elv.)used low #'s just a guess =1.59You need 1.5 to be fully stabilized. A change to 2690fpsonly changes it to 1.57 Twist is the biggest factor in stabilization, not speed.You can have a difference of 100 fps and only change the#'s by tenth's. With the new sleek design (elongated ogive) you needto really be careful of seating depth and concentricityof those bullets. Just because it's the highest B.C. bulletin the.264 class, doesn't mean you rifle will shoot it well.You could try the Hornady 147 ELD-M it's at .697 very closeand might be easier to find the sweet spot, if the Sierra doesn't work out. 1 Likes
Re: SMK 150 Grain 6.5 CM Reply #5 – January 08, 2019, 02:17:58 PM The hardest thing to calculate is the point at which the bulletgoes to sleep. Maybe just a few yards past the muzzle, or out beyond a hundred or so. Some groups suck at 100, but at 200 andbeyond, they find there life. And why most of my personal workis at 300. Fedex made it to my door just a bit ago. Here's the 150 SMK (1.480")against the 142 SMK (1.377") The 140 RDF falls right in between them in length.
Re: SMK 150 Grain 6.5 CM Reply #6 – January 08, 2019, 02:39:36 PM This is my setup. 1:7.5 twist 26" Hawk Hill Bighorn TL3, and specifically throated for these longer bullets. They are seated at .020 off the lands. I am going to possibly seat them out a bit...maybe to .010 but at .020 I had no pressure signs on the highest 44 gr superformance that got me to 2790 3 Likes
Re: SMK 150 Grain 6.5 CM Reply #7 – January 08, 2019, 03:10:19 PM My barrel was an 8tw running at low 2900fps to mid 2900's. I would say fully stabilized at that velocity but even so sometimes a bullet will perform better at a faster twist rate even though 'stable' at a slower rate, I have not tried them in my 7.5tw barrel and, since I am having a .284 built to serve the purpose I was testing the 150's for I may not end up trying. Your 7.5 twist is definitely spinning them fast enough for long range stability. In both of the barrels I shot them in (8 and 8.5tw) they shot best at 0.008-0.010" off light touch and groups opened up further off out to 0.030"...where I stopped testing seating depth as I wanted to keep the bearing surface completely in the neck. Now, when I mentioned them not grouping to my satisfaction that means consistent 5" of vertical with maybe some getting to 6" max over 20 shots in calm conditions (or at least not head/tail winds) at 1000yds and under 4" at 600yds. I wish they fit my bill because I would not be building a .284 if they did .
Re: SMK 150 Grain 6.5 CM Reply #8 – January 08, 2019, 03:50:02 PM I would start at your .020 off and work towards .005Hopefully you find a sweet spot. They seem to not like a lot of jump.That's a really nice setup you have.
Re: SMK 150 Grain 6.5 CM Reply #9 – January 08, 2019, 05:03:13 PM fuj mentioned the 150 with re 23 the other day in a thread... so I did a semi ladder test with them and re 23 in my stealth... seated them out long and using half gr jumps got them in the 2850 range before I seen any pressure signs and even then they were minimal... in that little test it looked like they was a wide flat spot around 2850 with them … I didn't pursue it any farther... just wanted to see how they acted with that powder... when I get a new pipe for the stealth I may see what they can really do with re23... I think it will do great... so xbonesny you might give them a good shake down with re23 in your stick... I feel it would do well for ya...
Re: SMK 150 Grain 6.5 CM Reply #10 – January 09, 2019, 06:49:42 AM This is all making my cabin fever worse....LOLAlright, after a huge stack of French toast this morning,I'm going to start sorting bullets. The points on this 500lot of 150's is excellent. Overall lengths are all over the map.I'll sort OAL first to establish lots, then do the base to ogivemeasurement......I posted an overall of 1.480" for the firstbullet I pulled from the package. A further look last night,I found one at 1.486", and one at 1.477". That was just fromsampling 20 pills. During that sampling, I did not run acrossanother 1.480".....Maybe dig out a few of the"Rush" albumsfor the process !!
Re: SMK 150 Grain 6.5 CM Reply #11 – January 10, 2019, 11:13:22 AM Did a chamber check in my Criterion to see where this 150 SMKwill hit the rifling. First off; My port on the Savage precisionaction that will let a loaded case eject cleanly is, 3.040". Doing5 passes, I'm getting, 2.962" I have a good .220" in the case neck.So if I test a few in FrankenCreed, I have some jump room beforegetting too far into the boiler room. I hope Mike still has my chamber cast and not melted down for something else. I'd like to replicate the chamber into the incoming Brux barrel. I am having a problem with checking base to ogive. The taper isso sharp, it's jambing in the tool with even a light touch. I startedto notice this with the RDF's but the 150's are worse. I'll be turning up a new gage just for this pill, and see what shakes.
Re: SMK 150 Grain 6.5 CM Reply #12 – January 11, 2019, 03:18:39 PM You might copy the Sinclair .260 insert with the tapered wall.
Re: SMK 150 Grain 6.5 CM Reply #13 – January 11, 2019, 04:13:53 PM Quote from: jvw2008 on January 11, 2019, 03:18:39 PMYou might copy the Sinclair .260 insert with the tapered wall.Found a quick and dirty work around. The Lee floating nose,seater plug, I honed to fit the RDF's, works. Just need to drillthe nose deeper to clear the tip.