Bullet Shape and Grain

R

RugerSteve

New member
Is there any noticeable reason for the different shapes and grains of bullets?
I have been reloading/shooting 115gr plated RN bullets.
Is there any benefits to shooting 124gr FN, or 147gr?
Seems line the FN would be less aerodynamic than a RN, so why use the FN?
My reasoning is, why spend more money on higher gr bullets, unless they are more accurate, but don't understand why the FN would be.
Also , why is there some places that sell 115gr .355, and there are one that sell .356? I have seen .355 & .356 for both coated and plated.
 
Where to start. Yes, there a difference. Aerodynamics does not affect handgun shooting because of the short distances; you need longer distances to see the effects of air on the flight of the bullet.

As for shapes, bullseye shooters use wadcutters, flat on both ends (like a can of peas), because they make a sharp circle when they pass through the target. They want every advantage to get a higher score should the bullet just barely touche a circle. Semi-wadcutters and truncated cones make a nice circle that isn't as sharp. USPSA and IDPA shooters use them instead of wadcutters because they feed reliably when they are shooting quickly (much faster than bullseye shooters). Compared to any of the aforementioned bullets, a RN sort of tears the paper leaving a less distinguishable hole. A cleaner hole makes for better scoring.

Heavier bullets and hollow points are longer and therefore have a longer bearing surface in the barrel making it more accurate.

A heavier bullet with the same power factor (momentum) than a lighter bullet has a lower felt recoil because the impulse is lower, i.e., the momentum of the recoil is spread over a longer time (because the velocity of the bullet is lower).

In general each gun has a preferred round, taking into account velocity and bullet weight and shape, that shoots better than other rounds. This is one reason why many shooters reload their own ammo in an effort to find the optimum round for their purpose in a particular gun. A bullseye shooters wants a round that shoots with the smallest groups. An action shooter doesn't require the same accuracy given that he/she is shooting quickly while on the run. They want a round that feeds reliably, producing the least recoil/muzzle flip, while cycling the slide as quickly as possible to get the sights back onto target to line up the next shot.

So now you know why I use a 147 gr FMJ-TC that I reload myself that just has enough velocity to make a bit over the minimum power factor for a production gun in USPSA and IDPA.
 
Thank you for pointing all that out. I am reloading for just mainly target practice right now. What about the difference between .355 and ,356. Is there really a standard that there is for the 9mm? I was told that .355 is usually for plated and jacketed bullets, and that if you see .356, that is usually a cast bullet. Reason I ask, is that I have been loading .355 plated and I want to try some of the coated bullets. Actually I just bought 500 at the gun show last weekend. Look fine , but checked by pulling one, and noticed some shaving of the coating was done I guess while seating/crimping. I have everything set up on the press where it is great using the .355 plated bullet and hate to have to run the powder funnel die down just a little more jto flare a bit more just for the .356, when everything has been running great. I was going to buy some Blue Bullets and notice they have them in .355.
 
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I don't mean this as snarky as it may sound, but your comprehension of ballistics will improve if you understand that "grains" is not a bullet attribute, but rather a unit of measure of the attribute "weight" (commonly) or "mass" (technically).
 
I realize that the grain is the weight variable of each bullet, just wondering what effect it has per each one, and which one is a more chosen weight. Also realize the .355/.356 is the diameter of the bullet itself. Don't worry, no snarkiness taken . I have a lot to learn reloading wise, and realize if I don't make slight adjustments to my press for different bullet weights , powder drops , coals etc, I will not get to the point of easily doing it, but I just like things easy. Set up and it's all set. Have been at this about a year, but just really started to making rounds by the 100's once I went from the Lee Pro 1000, to my new Dillon 650, about a month ago. I could make things easy by just sticking to my normal 115gr RN plated, at .355, but curious about the different coated 9mm's.
 
One thing to note is that just because a bullet is advertised to have a diameter of .355 or .356 doesn't mean that the bullets you receive are exactly that diameter. I have bought .430 bullets that measured .427 and .358 bullets that measured .356.

Most of the plated bullets I have bought usually measure in-between where lead and jacketed should be. In 9mm this would be .3555. I think this is ideal because a plated bullet is harder than lead but softer than a jacketed bullet

The lead bullets are usually advertised at .356 because lead is supposed to be .001 over bore. Lead is much softer than a copper jacket and will deform to fit the bore. You want it slightly oversized so that gases do not blow by the bullet and cause the lead to melt. If this happens you can getting leading of the barrel.
 
my longer barrel9mm pistols noticeably benefit in accuracy with heavier bullets. my small 9mm guns may or may not, I don't think I can shoot them consistently enough in a goup to tell a solid difference in accuracy. for small 9mm's, I can shoot any bullet better when it is loaded lighter than recommended, due to recoil, bte etc.

BUT, I have 9mm carbines that I shoot to greater distances and has a scope. out to 25yards, the 90-115gr bullets shoot amazing groups, but start to fall off out to fifty yards. the most accurate 50yard 9mm round for me, is a 147LCN loaded with a mid-high dose of HS-6. if you are shooting pistol distances, I don't know if you are oig to be alble to tell a difference in accuracy with different weight, just different point-of-impacts and different recoils, obviously speaking for properly sized bullets. if using lead, try to find a 9mm 125-147 sized to .357, they get squeezed into the rifleing and tend to leave the barrel straight.

most accurate "jacketed" bullet for me, 147gr Remington golden sabre with the "driving band", I thought it was a gimmick at first, but that little oversized band at the bottom of the bullet really seems to help.

sorry if I am all over the place with this post, just got back from vacay and ready for a nap. what I am trying to say is, try different profiles, but I don't think it makes a whole bunch of diff at 10yards and under. try different weights and you may see you can actually get better results from larger bullet, likely due to larger bearing surfaces, even at 10yd and under. start getting to 25-50yards, you'll find that weights and profiles start making a bigger difference, like loading or a rifle, and there will be no easy formula to what your gun is going to like the best, just try them all in "popular" profiles in the different weight classes and see what does you best. then when you find a weight that works best, then start narrowing down powders, profiles and powders.
 
I will try to keep this very generic, yet cover the points, mostly. My comments are in 'RED'.

"Is there any noticeable reason for the different shapes and grains of bullets? Yes.

I have been reloading/shooting 115gr plated RN bullets.
Is there any benefits to shooting 124gr FN, or 147gr? Generally, lighter bullet weight will provide a higher muzzle velocity and energy over a heavier bullet weight. However, more bullet weight normally translates to greater mass. Greater mass will provided greater momentum. So what? A heavy bullet will have a slower muzzle velocity but the greater momentum will maintain greater amounts of velocity to longer ranges and will over take the lighter and faster at the muzzle bullet's velocity at some point. In short, heavy bullets will shoot farther than light bullets.

Seems line the FN would be less aerodynamic than a RN, so why use the FN? Pointy bullets will have less drag, both in the air and in the tissues of a target. A pointy bullet that slips in and out of your target, 'paper', make no difference. But that rabbit or deer or bear, it makes a lot of difference. We want as much energy transfer into the game animal as possible. And as stated above, square edges make for nice round holes in paper for scoring.

My reasoning is, why spend more money on higher gr bullets, unless they are more accurate, but don't understand why the FN would be. Bullets vary greatly, as much as barrels, but not as much as differing loads (just too many options). Your weapon/s will be the end determining factor in this. If you pet weapon groups best with one bullet weight/type/loading, that's what you should be shooting. If not, change the many variables to find what works. Fortunately, those who came before us have tested and re-tested and general 'works better' combinations are general knowledge. Try what others have found that works but don't get stuck on just one, try several.

Also , why is there some places that sell 115gr .355, and there are one that sell .356? I have seen .355 & .356 for both coated and plated." Just more variables. Lead bullets generally will work better when over the true size of the bore by .002th, give or take. Here comes one of the biggest spreads. From the bullet weight and types listed, I am guessing the weapon is a 9MM. How many different standards, ie. bore diameters, have there been in the last 110 to 120 years for the 9MM? Add to this the sometimes sloppy standards of war production and the need or desire for several bullet diameters come into play.

Further, the normal pistol ranges are too short for 'ballistic coefficient' of the bullet to come into much play. Yes, Ed McGivern was shooting 1000 yards with his .38 Special in the 1930's, but he and Elmer Keith were exceptions.
It comes down to two things. What are you shooting, target wise, animal or paper and how much are you willing to spend on each shot. Your option.

Load with care and enjoy,

OSOK
 
Each shape bullet is designed for different purposes. Round nose bullets feed quite reliably in semi-auto pistols. Flat nose bullets have more terminal effect on target. Wadcutters and Semi-Wadcutters cut nice round holes in paper targets. Semi-wadcutters are stable at longer ranges, but still have good terminal effect on target. Different weights will react/preform differently at different distances/ranges (some will start out very fast but loose velocity rapidly while some will start slower but retain velocity better [AKA ballistic coefficient and sectional density are terms used to describe these traits]). Some designs are more accurate than others, and some work better than others at extended ranges. Some bullets are just designed for "shooter appeal" and manufacturer's follow trends just like any other business. These are just generalities as each bullet noted will have more than one or two uses (I use a "target" bullet, wadcutter, as a self defense bullet). Most reloading manuals will have a section on bullet design and use. Many choices are just plain "it looks good to me" choices, which is cool too...
 
You mentioned shaving your bullets. Are you seating and crimping in one step? It's possible you have enough flare in the case mouth, but might be crimping the mouth while the bullet is still being seated.
 
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