Does a heavier bullet help accuracy?

[Mac Attack]

I shot my first set of 30-06 reloads today and they were fairly accurate in my boat. Using a 150 grain Hornady Interlock SP's over a charge of 45. grains of Varget I was able to hit everything I was aiming at and more. Before I reloaded my 150 gr SP's I read all the reloading 30-06 threads on this forum and the CMP forum. It seems most of the people who reload for their M1 Garands use the 168 grain HPBT's Match Kings and swear by their accuracy. So my question is, does a heavier bullet help with accuracy? In my case, would I benefit from a 168 gr MK bullet over my 150 grs? Thanks for your advice.

[Jonathan Doe]

It is not just heavier weight matters. It is the construction of the bullet and its consistency. Also coupled with the right rifling twist rate will give you a good accuracy. Try 155 brain Sierra Match King also.

It will be better if you know your rifle's twist rate.

[Mac Attack]

I am shooting them through a M1 Garand. A quick google search relieved:
4-groove,right-hand, 1 in 10"

[Jonathan Doe]

I am shooting them through a M1 Garand. A quick google search relieved:
4-groove,right-hand, 1 in 10"

In this barrel, either 168gr or 175gr Match King will do a good job. I have a Krieger barrel with 1-11" twist, and it shoots both bullets extremely well. I shoot 168 for up to 300 yards, and 175 for 300+ yards.

[Divernhunter]

Topgun7----Are you shooting them in an M1 Garand??? Generally I would suggest staying close to the mil load (147gr) and use 147-155gr bullets(or if you must a 165-168gr) and a powder with a buring rate close to the original which was IMR4895. Imr4064 is another good one and Varget is in that range.
I use only IMR4895 for any of my 5 M1 Garands and 150gr bullets to be sure I do not damage the operating rods in them.

SO unless you need to for match shooting and are willing to replace parts stay with ammo designed for the M1 Garands gas system. That means about 150gr bullets and IMR4895 or close to it powders. Some people will insist on using mil spec primers but I have not had any slam-fires with commercial LR primers.

[znode]

A bullet with a high sectional density has a higher ballistic coefficient, which makes it more stable to atmospheric effects, assuming you can still push it fast enough (for flatter trajectory and more time to transsonic barrier) and spin it fast enough (for gyroscopic stability).

So yes, a heavier bullet can, though not always, help accuracy.

[Jonathan Doe]

Topgun7----Are you shooting them in an M1 Garand??? Generally I would suggest staying close to the mil load (147gr) and use 147-155gr bullets(or if you must a 165-168gr) and a powder with a buring rate close to the original which was IMR4895. Imr4064 is another good one and Varget is in that range.
I use only IMR4895 for any of my 5 M1 Garands and 150gr bullets to be sure I do not damage the operating rods in them.

SO unless you need to for match shooting and are willing to replace parts stay with ammo designed for the M1 Garands gas system. That means about 150gr bullets and IMR4895 or close to it powders. Some people will insist on using mil spec primers but I have not had any slam-fires with commercial LR primers.

I shoot M-1A. My shooting team partner used to shoot McCoy M-1 Garand with those bullets.

[Mac Attack]

Thanks for the info guys. I think I will load the 150's for general shooting and will try some 168 SMK's for longer distance shooting. As a plus, the Varget powder charge for the 168's is only a grain or two more than the 150's so I don't have to make significant changes to my powder dispenser.

By the way, the Schuster adjustable plug is a great accessory if a person wanted to shoot non mil ammo in their Garand. I set it up to shot my reloads and it functioned perfectly. I then tried some HXP '67 M2 ammo thinking it would not cycle because the plug was adjusted to my reloads. Low and behold it functioned just fine. So now I wonder if I needed the plug or not. However, since I am planning to shoot 168 SMK's I think the plug will be necessary.