Flat or Bevel Base bullets

I've been casting a lot of bullets lately and have purchased some new molds. For the sake of discussion which is more accurate, flat or bevel base bullets, and why?  I have gotten some of my flat base molds to cast very sharp corners with a touch of flash to them. I use a chamfering too to take that flash off. This puts a very thin chamfer on the corner of the flat base. Is that enough to make it perform like a bevel base bullet? They sure load better that way.

Ive had both types be very accurate, I don't think it makes a difference that amounts to much if any.

I have alot pistol bullet moulds with bevel base or gas checked ( shot without GC installed) all are accurate from a several  different guns in each caliber.

Ah yes, the old gas check bullet without the gas check issue that comes up on Cast Boolits Forum from time to time. I've been shooting them that way for years with good results. The way I see them it is a flat base bullet with a rebated boat tail. I was pretty well convinced that it was easier to cast good flat based bullets than bevel based designs. Then I discovered that if you cast either design with minimal sprue material on top of the sprue plate, both the bevel and the flat base bullets cast more true to the bullet design. My theory is that the small puddle shrinks less as it cools and doesn't pull metal from the base of the bullet. This allows clean even bevels and flat bases. Im about at the point where I think the bevel bases might be more accurate just because they load easier into the case and result in more concentric loaded rounds. Difficult to say for sure.

Interesting thoughts

IMHO I think flat based bullets are more accurate.  All else being equal.  I think they get a more consistent departure from the barrel without skewing.  Proper case bell and seat from the shoulder will minimize any case/bullet misalignment during loading.

If I had a choice, I would ONLY buy flat base bullets and molds. The most important part of a bullet for accuracy is the base. If I have a flat base without any dings, I know that it will produce the best accuracy it can. Flat base is just easier to inspect and see the flaws, whether or not it is inherently more accurate or not.
Like rifle bullets where, if I'm shooting under 300 yards, I stick to flat based bullets and only use boat tails for long distance shooting. Flat based just seem more accurate at shorter distances than boat tail bullets. Never had a problem seating a flat base bullet so saw no need to go to a boat tail, except where it had an advantage.
I also do NOT size any of my cast bullets. They are only tumble lubed and loaded—actually, I don't tumble lube them as I always think that the bullets hitting each other might damage the base, so I hand "shuffle" them in a glass casserole dish and do about 500 in about 1 minute). 
I ran a whole bunch of tests back in the '70s (9x19, .45 Auto, and .44 Mag) and I found that my as-cast bullets (hand lubed at the time, as I hadn't heard of pan lubing yet and tumble lubing didn't exist) were always as accurate or more accurate than the bullets I sized and lubed (based on 5-10 5-round groups). I got over-size bullet sizing dies to use in the Lubri-Sizer, until I started pan lubing all my pistol bullets (kept using the lubri-sizer with slightly over-size dies for all my rifle bullets).

All that prep might show a difference at 300 yards but not at 50. If your out for the best accuracy, ditch the lead and go with 185-fmj-hp from zero or nosler.

^^  That is correct  ^^

So, what did Hershel shoot???

Boy, there are some veryed responses. In my experience, I've found it really depends on the gun. I know my gun will ransom rest a 100-10x (50yds) with 185gr flat base lead bullets I buy locally. I know it will shoot 100-10x (25yds)with some old star swaged bevel base bullets from my hand. I've seen a high shooter stop shooting free supplied 185gr Zeros and go back to lead because his gun didn't shoot the jacketed as well. I think you and your gun have find this out for yourselves.

^^^ That's also correct  ^^^^

people get overly obsessed about accuracy,  if your gun shoots 3'' at 50 yards you could shoot 2700 if you have the talent, many don't know a recent national champions gun was tested after he had won camp perry with his loads and everyone was surprised its best group was 3.5''

DavidR wrote:people get overly obsessed about accuracy,  if your gun shoots 3'' at 50 yards you could shoot 2700 if you have the talent, many don't know a recent national champions gun was tested after he had won camp perry with his loads and everyone was surprised its best group was 3.5''

Bill Blankenship discussed that very thing in one of his articles in "The Pistol Shooter's Treasury".

Well it sounds like its hard to go wrong. Just work on it until you find what your gun likes.