Flat vs Round

[Super Sneaky Steve]

Hello everyone.

I've done lots of testing with a lee mould C309-180-R for my .308 Winchester rifle. I get the best accuracy at the lower end of the scale and I clocked it going 1761fps.

My question is, should I start the testing process over with the C309-170-F mould to take advantage of the meplat or will it not make a difference?

I know shot placement is key, but that said, would the flat nose perform better all things equal?

All my lead is scrap of unknown origins but shoots a good group without any leading.

This load will be for deer.

Thanks!

[Adam10mm]

I like flat meplats on my hunting bullets. I don't think it's a big difference, both will kill. Round is probably better for longer range.

[petroid]

I would think that weight and velocity would be fine with a RN.

[jhalcott]

One time a friend asked what difference does the nose shape make on a bullet. I took a round nosed bullet and shot a water filled gallon jug HANGING at 100 yards. I Loaded another cartridge with an IDENTICAL bullet/load except for a flat I filed on the nose. The water filled jug( less the water that dripped out the RN hole) exploded into several pieces! the lid went about 30-49 feet into the air. SAME bullet, same load but dramatically different results. I can not say YOUR results will be the same, but I'd test what ever load you come up with on wetpack at the distances you plan to shoot game. This will give SOME idea what to expect from penetration and accuracy.

[Lonegun1894]

If you knew it was soft, I would think either RN or FN would work, with preference going to the FN, but with unknown alloy, I will go with a FN every single time--even if it does cost me a little bit of range, cause most hunting shots aren't far enough away for the RN to have any advantage in flight, but the FN always has the advantage over a RN when it meets flesh.

[Super Sneaky Steve]

I started over with the flat nose design. Here's my first test. Accurate 5744 powder was used with 22gr, 26gr and 30gr. It's obvious which was the winner. If you take out the flyer those four shots were almost 1/2" at 100 yards.
http://i1103.photobucket.com/albums/g463/Stevenk999/5744.jpg (http://s1103.photobucket.com/user/Stevenk999/media/5744.jpg.html)

[runfiverun]

you could probably take that flyer out before you pulled the trigger.
feeling your neck tension when seating, and weight sorting the boolits into groups of about the .2-.3 range will help a lot.

oh the original question.
flat nose for hunting.

[taco650]

you could probably take that flyer out before you pulled the trigger.
feeling your neck tension when seating, and weight sorting the boolits into groups of about the .2-.3 range will help a lot.

oh the original question.
flat nose for hunting.

I'll have to second R5R's suggestion (the first one) about weight sorting your casts to tighten your groups. He and a few other members have been working on a little project cartridge they call 30XCB. Reading through their thread on it, I've learned the value of watching the details.

I think the FP boolit would kill a little better too.

[quilbilly]

There are no degrees of dead. Either should work just fine.

[Blammer]

there's a lot of space between 26gr and 30gr, I'd test some with one grain increments between 26 and 30 to see if you get decent accuracy with any of them. The extra velocity wouldn't hurt.

I'd go with the FN design for hunting, but I've used RN too and it worked.

If using the RN I'd aim for bone coming and going.

[jhalcott]

I've run into the problem BLAMMER speaks of. Some times the barrel vibrations are equal at different powder charges. Going one grain at a time MIGHT show a good group at a higher velocity. Accuracy, repeatable accuracy, is more important to ME than a bit higher speed. I test hunting loads for both penetration and accuracy. After that I break out the Chrono!

[quilbilly]

Perfect timing. I just did a terminal ballistics test this morning with my 308 and Loverin style 162 gr RNGC at a muzzle velocity of 1820 FPS. The distance was 40 yards and the medium was soaked compacted phone books (much more solid than a deer) with an 1/8" piece of plywood at a depth of 1 inch to simulate a clipped rib bone. Penetration was 13-1/2" + or - one inch and expansion of all were to .65" or .75". Weight retention was 90% to 105% (probably a piece of phone book). The alloy was 60% pure, 37% chilled hard bird shot, and 3% tin. With that type of expansion and weight retention, that extra meplat is unnecessary out to at least 125 yards. The only problem with the test was that I had to shoot extra because the boolits were going through the same holes.

[runfiverun]

meplat size also determines a boolits effectiveness at velocity.
the more velocity the less flat diameter you can get away with.

[quilbilly]

meplat size also determines a boolits effectiveness at velocity.
the more velocity the less flat diameter you can get away with.
Absolutely true! I did a similar test some years back with 30/30 and a 160 RNGC at 1550 FPS in the same medium at 40 yards and got 17-18" of penetration but little expansion although the boolits did tumble making a nasty "wound channel". From these two tests, I would use the flat point at velocities under 1700 FPS and the round point at higher velocities for the same effect on the game (recoil is markedly different though).

[Pilgrim]

Just something to ponder....If the round nose was the better bunting boolit, why did they start making FP boolits. FP is not as aerodynamic as the RN, and may not be quote from as accurate. Gotta be a reason, right?

[quilbilly]

The point I was making was that if you think most of your shots will be under 80 yards and you prefer not to deal with much recoil, a flat point at 1550 MV will work just fine and it will feel like a popgun (plus fun to shoot a lot all year). On the other hand, if you don't mind the extra recoil and might get longer shots, use the round nose at a higher velocity for the same effect. Both can work exceedingly well in the hunting situation you think you will run into and high velocity can be a bit overrated. No worries with either. Whatever floats your boat. For me this is all academic since I only hunt deer with a 45 cal muzzleloader using PRB anymore in an area where a bayonet is sometimes appropriate. I have always been told that historically flat points primarily became for tubular magazines once the smokeless powder era began.

[facetious]

Just something to ponder....If the round nose was the better bunting boolit, why did they start making FP boolits. FP is not as aerodynamic as the RN, and may not be quote from as accurate. Gotta be a reason, right?


Just speculation : The invention of the lever action rifle and flat point ammo for them. At some point some one noticed that thy worked better for hunting.

[jmort]

I don't think many people got the message of the meplat until Veral Smith came along with LBT.

[Lonegun1894]

I got the message of the meplat when a friend introduced me to the Gospels of St. Elmer, and the earlier ones of those were written before LBT, although I have also read a lot about Veral Smith and he has also done a lot of amazing work, so I figure he picked up where Keith and his contemporaries left off.

[jmort]

Keith worked with SWCs, i.e. fairly small meplats. It was Veral who made the meplat what it is today. Both are worthy creators.

[Lonegun1894]

You're right. Keith's were definitely smaller than Veral's, but in reading his books, although he was kinda stuck on SWC designs, he was going to larger and larger meplats as time went on. The way I see it, Veral took what he could use from Keith's experience and designs, and kept going. And you can only go so large with the meplat on a SWC before you do away with the sharp shoulder unless you go to a wasp-waist design, so Veral took the next logical step, and I'm glad he did, cause in another 100 years, they will be discussing them both as great bullet designers from way back when.