Alycidon Posted May 24, 2008 Report Share Posted May 24, 2008 Here is something that may be of use to the 20BR/20PPC boys. http://www.thegunhaus.com/bullets1.html A 60 grain pill, not quite sure what twist you would want, 50 grain is 1 in 9 so I would guess 1 in 8 maybe. If anybody has tried them I would be interested in getting hold of a few to try. A Link to comment Share on other sites More sharing options...
pat Posted June 11, 2008 Report Share Posted June 11, 2008 For the shooter with a medium large to large case and a 1-9" twist barrel They seem to think that 1 in 9 twist should do With a quoted BC of 0.4 (if you believe it) it should have long legs, but since it possesses neither ballistic tip nor hollow point, expansion is going to be somewhat slower, which might limit its usefulness.... might be OK on the foxes but will probably just make neat .204" round holes in smaller critters. Cheers, Pat. Link to comment Share on other sites More sharing options...
Alycidon Posted June 14, 2008 Author Report Share Posted June 14, 2008 1 in 9 is recommended for Berger 50 grain bullets, they will stretch to 600 yards at least, some are saying 800 yards. The 60 grain would probably want a faster twist, the benifit would be less wind drift not that is a large issue with the 50 grain. Todd Kindler recons that a 55/60 grain bullet would be ideal for the bigger 20 cases. Match type bullets work just fine on rabbits foxes etc, expansion tends to vary a bit depending on if the bullet strikes a bone etc. I have killed foxes with a 6mm and hardly left a mark on them with a Vmax that normally expands well, I have had others with match bullets that have really let rip VMAX style. A Link to comment Share on other sites More sharing options...
6mmBR Posted June 14, 2008 Report Share Posted June 14, 2008 Just seen this on the 6BR site. Berger are to produce a 55gn .20 bullet with a BC of.4 Erik Stecker of Berger Bullets confirmed that his company will be producing a new, high-BC 20-Caliber bullet this fall. The new bullet features a conventional, non-VLD tangent-ogive design for greater seating flexibility and, hopefully, increased precision. The new bullet should be the highest-BC bullet available to 20-Cal shooters from a major bullet-maker. Although production dies aren’t ready yet, Berger has set a 0.400 Ballistic Coefficient design goal for the bullet. That would be a significant step up from Berger’s current 50gr, 20-caliber bullet, which has a published BC of 0.295. We expect the new 55-grainer to require an 1:8″ or faster twist barrel, but the exact twist required will depend on the final bullet dimensions when it is put into production. Expected ship date for the new 55gr bullet is “late August to early September”, according to Stecker. With the correct-twist barrel, the new bullet should work well in most popular 20-caliber chamberings, including 20 VarTarg, 20-223, 20 PPC, 20 BR, and .204 Ruger Cheers Dave Link to comment Share on other sites More sharing options...
Alycidon Posted June 15, 2008 Author Report Share Posted June 15, 2008 1 in 8 is pretty specialised, 1 in 9 was hard enough to come by, none of the European makers make them. But there are US barrel makers that will build exactly what you want so it wont be an issue but most 204/Tac20s etc are 1 in 11 or 12 at present and may need a retube. Mind you the faster twist should still shoot the 39/40 pills OK but they will be having a fair jump to the bore. I have run ballistic charts for it to see how it stacks up using the BR case, http://www.biggameinfo.com/BalCalc.aspx. 250 yard zero, 10mph full value wind. 50 gr Berger (.295 BC) at 3800 fps 55gr at 3500 estimated. Drop Drift Drop Drift 300yards 2.4 7.4 2.6 5.8 400 yards 10.7 13.8 11.2 10.7 500 yards 24.0 22.7 25.3 17.4 600 yards 53.0 34.6 45.8 26.1 800 yards 120.0 69.0 111.6 50.6 All measurements in inches. I cant get this to appear how I have typed it, however the first two figures beside a range are the 50 grain drop and drift, the second two the 55 grain drop and drift. perhaps one of the moddys can improve how it reads. Its wind rather than drop that causes most longer range errors, as you can see the 55gr cuts drift at distance. A Link to comment Share on other sites More sharing options...
6mmBR Posted June 15, 2008 Report Share Posted June 15, 2008 Looking at your figures it seems the 55gn bullets drop by 17% less than the50gn and windage the 55's are effected 27% less. Thats pretty impressive. .4 is one hell of a BC for a small bullet, thats the same B.C as my 87Vmax in 6mm. Cheers Dave Link to comment Share on other sites More sharing options...
Alycidon Posted June 15, 2008 Author Report Share Posted June 15, 2008 The 50 is a odd looking bullet, almost like a fat needle. The ballistics for the 50gr outperform the .22 Swift over 300 yards, this 55gr just opens the gap wider. Under 300 yards though there is little to choose between them. A Link to comment Share on other sites More sharing options...
craigyboy Posted June 16, 2008 Report Share Posted June 16, 2008 if serria/hornady/nosler would come out with a heavier ballistic tip 20 cal bullet we would be cookin on gas, a 55g v-max in .204 would hold a very high bc nd make a great longer range cartridge, I know if something like this came on the market I would have a 20 satan built around it to sit along side my tac20. Link to comment Share on other sites More sharing options...
Alycidon Posted June 17, 2008 Author Report Share Posted June 17, 2008 Todd Kindler is leaning on all the US bullet makers for a heavier weight fast expanding 20cal bullets. The downside of Satan may be an inabilty to see impacts unless you build it very heavy, don't really know for sure as I have not personally yet fired the 6x47 parent case. Dont quite know what barrel life would be either, suspect not much more that 600-800 rounds, quite a bit of powder going up a small hole. Mind you if you do build one we will be queuing up for a blam with it !!. A Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.