square vs. round bottom rifling

[tdiem52]

What are the advantages, and disadvantages of round bottom vs. square bottom rifling.

 

[galamb]

Round bottom rifling has less corners/nooks/crannies to trap fouling so it's often easier to load and you may be able to shoot a few (more) rounds before you have to swab (according to the builders of such).

According to most target shooters, square bottom rifling will result in a more accurate shot.

I have both. I didn't choose one over the other because of any of the various reasons tossed around.

The barrel length and profile is why I buy the barrel regardless of the rifling type.

On one build I wanted 7 groove rifling to mimic the original. Rice cuts 7 groove and the barrel happened to be round grooved - no more complicated than that as far as that selection went.

I use my rifles for hunting and plinking. I don't notice any accuracy difference due to rifling - length of the barrel has far more impact on my shooting accuracy.

Likewise, I don't find the round any easier to clean than the square - procedure is the same - loading is easy with both etc etc

But I'm not match shooting or firing a hundred balls a day - maybe that would make a difference.

 

[ghostdncr]

Same here. My Colerain .45 has round-bottom rifling. My Green Mountain and Pedersoli barrels have square bottom grooves. The way I shoot, neither has shown a real advantage over the other. It just worked out like it worked out.

I guess if a fellow was into competition shooting, the square groove may be better. Living rough and cleaning as best one could in the evenings, round groove may be better.

 

[nkbj]

And round grooves mean that the bullet doesn't have to expand so much to fill the rifling.

 

[roundball]

Pretty much touched on most things...I've found them easier / faster to wipe clean, easier to seat a ball, easier to pull a ball, and couldn't be more pleased with the accuracy.
Since trying my first round bottom groove barrel, every one since then has been round bottom, always will be.
Others mileage may vary...

 

[hanshi]

Basically I simply find them easier to deal with, cleaning, patching, etc. I only have one rb barrel and if I get another rifle it will also be round.

 

[tenngun]

And round grooves mean that the bullet doesn't have to expand so much to fill the rifling.

I have 0 experince with round bottom and have never owned one. I expect your post referes to minnies ...why is it easier?

 

[nkbj]

And round grooves mean that the bullet doesn't have to expand so much to fill the rifling.

I have 0 experince with round bottom and have never owned one. I expect your post referes to minnies ...why is it easier?

Not minies, flat based bullets with lube grooves or paper patched. With them when the powder charge goes off there are two things that are prone to happening: The slap on the behind causes the sides to swell outwards to seal off the gas flow and the incandescent jet of particulates laden gases try to escape around the sides (to cut the side off the bullet, spray lead down the bore, boogering up the works).

This is an over simplifying illustration but imagine the gray is the bore and the red is the extra space that the lead has to fill up with square bottom rifling.
By the way, those corners also become the location of minor lead stringing that inhibits thorough surface washing on a localized basis which creates localized pitting that creates more leading (and on and on).
My 24" twist .458" bore TC New Englander has grooves that are a little deeper than they need to be for shooting standard off the shelf 45-70 type molds but they are round bottomed which helps in preventing gas cutting as well as in cleaning and the depth of groove makes the barrel work with round ball also.
In this case you could say 24" is a "compromise twist"! :haha:

 

[Rifleman1776]

What are the advantages, and disadvantages of round bottom vs. square bottom rifling.

Since the dawn of the earliest rifles, the debate over the best style, rate of twist, number of grooves, etc. has been non-stop.
Pick yer pizzen and decide fer yerself.

 

[nkbj]

This is what the New Englander looks like.

 

[Rifleman1776]

Don't know the caliber but it looks T-Rex potent from here. :shocked2:

 

[nkbj]

Don't know the caliber but it looks T-Rex potent from here. :shocked2:

That's the south paw TC New Englander with a .458" bore diameter to use with off the shelf 45 caliber mold designs as-cast from soft lead lubed or paper patched.

 

[mrremington]

Im also interested. Most of the comments have been for conical bullets. What's the difference when using patched balls? I'm planning on building a 32 cal flintlock and am trying to decide which barrel would be the better choice.

 

[nkbj]

From what I've seen so far we oughta grab any bump we can get on cleaning. Why wouldn't we want round bottom? Really, why not?

 

[mrremington]

That's what I was thinking.

 

[roundball]

Most of the comments have been for conical bullets.
What's the difference when using patched balls?

I think there's been some back & forth posts in the thread about the one initial conical post which might drive up the post count if looked at that way, but in general round bottom grooves seem to be pretty much associated with patched balls...and taking off on what Good Cheer said, once you've used both I'd be very surprised if you wouldn't want round bottom groove barrels from that point forward.
Now, to be clear, my Rice round bottom barrels did cost around $40 bucks more than a comparable Rice square groove, but speaking for myself I'd quickly give up a few burgers & fries to pay the difference.
Others mileage may vary...

 

[mrremington]

I was on there website. I'm not to concerned about $40 extra bucks and it would be my first round bottom barrel. I can't wait.

 

[galamb]

I only shoot round ball. I hunt and plink - no serious target work.

I don't patch super tight - never needed a mallet or the help of a buddy to get the ball/patch started.

I don't shoot coned barrels and I hunt with what many would consider "lighter" charges.

(75 grains in my 50, 60 grains in my 40 are my hunting loads for deer).

I am more than happy with 2" groups at 50 yards - sight in at 75 and my all time long shot on a deer was 27 yards.

Next build is waiting on a Southern Classic swamp from Rice (maybe ready next month, ordered back in November) - wanted the profile and the number of groves to emulate the inspiration rifle.

Had the option of square or round rifling since it was ordered - chose round even though it was an extra 40 bucks ($265 vice $225) - if you get a Rice it may as well have round rifling - just because that's what Jason is known for.

Most of my rifles are square bottomed. Not tough to load, not tough to clean and don't see any accuracy difference between them and the round rifled ones.

When asking the question "which is better" all you are ever going to get is opinion.

I will never be capable of shooting my new Rice barrel to it potential.

A Green Mountain costing almost 100 bucks less would still out shoot me and if I could have got the profile from them that I wanted, I would have saved the 100 bucks.

You need to shoot both types of rifling for a bit to decide for yourself "which is better FOR YOU".

I love Ford Trucks - owned a few, but currently drive a GMC because the price was right and it met my needs. Treat my barrel choices the same way...