Velocity curve and you'll see after 900fps there is a pretty dramatic increase in dbs as the bullet increases speed. In other words, the air accelerates at the surface of the bullet as the bullet pushes the air out of the way, which creates supersonic fluid flow, which creates a supersonic crack that makes the makes the bullet still really loud. Long story short, a subsonic bullet can still create a supersonic pop because the air around the bullet is increased above the speed of sound as the bullet cuts through the air. I suggest running 900fps or less if you really want good subsonic performance. I'll take it.įor plinking at 40 or 50 cents a round, they work better and are cheaper than anything else I've tried. Some people knock VV for their price but 6300 loads per 8. Very little smoke, no unburnt powder at all, no flash, clean cases, not a bunch of residue left over like some factory loads I've shot. If I wanted high performance subsonic defensive ammo I would be loading a handful of Lehighs. I'm sure those numbers would come down had I hand weighed each charge but I'm looking for something I can pump out quick and cheap. Drop # averaged of 8 drops then verified at 1 and 5 of the 10 charges. ![]() These were all loaded with a LNL press with powder drop. I would guess case capacity was around 70-80% after bullet seating, and was causing the burn rate to fluctuate. However with the High ES and SD numbers I'm going to reload a bunch at 9.0, 8.9 and 8.8 and try to reduce seating length to increase the efficiency of burn rate. Most accurate load for me was 9.0 and all stayed subsonic. For me at 50 yards, best load shot just under an inch with an ES (66) and SD(20.1) Powder charge of 8.9 was right at 1050 fps. The Mk262 clone loads failed but 300 blk sub loads with 190 grain noslers and VVn110 did much better.ġ90 grain data was spot on. In 223 with a 14.5" barrel getting 500+ below published data from nosler and Sierra. I was actually surprised with the HUGE difference in speed of published loads. Lots and lots of guys on 300blktalk have played with 1680 and CFE BLK for heavy supersonics so might want to take a look at their experiences.So we went out today in the pouring rain and shot a few loads. You can play a little bit, try loading them at 2.22" and see if they feed and cycle fine, it'll allow you a slightly higher charge and lower pressure. ![]() Well it'll really depend on your COAL, because AA1680 and CFE BLK don't mind being slightly compressed but you'll have to watch for pressure sign.ġ68 SMK 2.18" 19.2 - 19.7 -> Be careful 19.7 is max book load.ġ75 SMK 2.18" 17.8 - 18.4 -> 18.4 is max load. Obviously a good chrono is a must when loading subsonics. I prefer to be in the 980-1020FPS range but some people like to be in the 1040-1060 range, it really depends on your outside air temperature. ![]() Now I can run Lapua 200gr with 8.3 gr 2.15" OAL and still be in the magic 1000-1020 FPS range and hold the bolt on last round.įor 220 GR with N110, start at 9.0-9.5gr and work your way down to 8.0-8.5. Stock I couldn't get it to cycle reliably with those fast powders unless I used heavy SMK 240s and run them in the 1080fps range. My 10" Noveske has no issues now that I use a JP SCS with the tuning kit and Faxon Low mass BCG. ![]() If you have a can, it'll help a lot, otherwise it might still work depending on your GB port size, BCG and buffer balance. But n110 is a faster powder than 1680 or CFE BLK so you're on the edge of reliability for a typical 300blk gasser.
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