Where's my Land and Groove?

[swathdiver]

Pietta "Sheriff", the .44 caliber 5-1/2" model has SIX lands and grooves.

Pietta NMA, the .44 caliber 8" model has SEVEN lands and grooves.

How long has this been going on??? Why???

 

[Tommygunn]

Yes? So? What is your point? I have a lot of guns and I think many of them probably have a different ## of lands/grooves. I wouldn't be shocked if they had different direction twists, either.

 

[Doc7]

My Marlin has Micro Grooves

 

[loose noose]

My Marlin has Ballard rifling, which is better for shooting lead bullets that I cast, over the Micro Groove.

 

[Rattus58]

My Marlin has Ballard rifling, which is better for shooting lead bullets that I cast, over the Micro Groove.

why so? I thought micro-grooves just needed an oversized bullet and sometimes a gas check to be accurate?

Aloha...

 

[303tom]

Pietta "Sheriff", the .44 caliber 5-1/2" model has SIX lands and grooves.

Pietta NMA, the .44 caliber 8" model has SEVEN lands and grooves.

How long has this been going on??? Why???

If you really think that is odd, maybe you should check this out...................

 

[rdstrain49]

I doubt that Ballard cut will out shoot Micro. My 336 with Micro will shoot 1.5" groups at 200 meters with cast gas check 172 gr. bullets.

 

[rifle]

From what I understand the micro groove was for jacketed bullets and leaded up when used with lead bullets. The Ballard type rifling is made for lead but....I thunk, can shoot jacketed too.
The micro groove with a gas check bullet seals the gases and stops the gas blow-by that washes lead on the barrel. I think the barrels can still lead up especially if the lead used is soft. Extra hard lead bullet alloys probably work the best ,I'd say, in micro groove barrels.

 

[StrawHat]

Micro groove barrels do fine with lead bullets. Cast from a softer alloy and from the correct mold, no leading. As for which is more accurate, that is usually determined by who is squeezing the trigger!

 

[rdstrain49]

Ain't that the truth.

 

[Driftwood Johnson]

Howdy

While it is easier to measure the groove diameter of a barrel with an even number of grooves, there is no rule that says all barrels will be like that. Smith and Wesson has been making barrels with on odd number of grooves for over 100 years.

 

[swathdiver]

I was curious as to why Pietta would take the same gun, one with a shorter barrel, and make it with different rifling. Was wondering aloud if it was something new or had been going on all along.

 

[Skinny 1950]

.44 Cal. rifling from a reproduction M1860 very close to the original progressive rifling produced by Colt:

 

[AbitNutz]

I wouldn't mind having an octagonal, odd groove, progressive twist rifled barrel on my ROA. Maybe like 5 grooves...for no particular reason.

 

[Foto Joe]

In my experience the Marlin Micro Groove barrels don't like Black Powder to be pushing the bullet out the hole. The first few shots are dead on, after that about the only safe place to be is directly behind the gun 'cause I haven't a clue where that bullet will end up. The fix is to run a patch with Ballistol on it down the tube after four or five shots but it's a pain.

I found a Buffalo Bill commerative last year in 45-70 and the only thing that stopped me from buying it was the Micro Groove rifling, that and Marlin didn't exactly go over the top on that particular commerative.

 

[loose noose]

Foto Joe, said it right, the micro-groove rifling just don't cut it with BP loads and lead bullets. (basically what I said in a previous post, but somehow got deleted). I cast .310, after they are resized, and use Lyman Gold BP Lube, in a 170 grn bullet. Using lead wheel weights; I've used 30-35 grains of 3F Goex powder and have gotten 2" groups at 100 yards quite consistently, from the bench.

 

[Rattus58]

In my experience the Marlin Micro Groove barrels don't like Black Powder to be pushing the bullet out the hole. The first few shots are dead on, after that about the only safe place to be is directly behind the gun 'cause I haven't a clue where that bullet will end up. The fix is to run a patch with Ballistol on it down the tube after four or five shots but it's a pain.

I found a Buffalo Bill commerative last year in 45-70 and the only thing that stopped me from buying it was the Micro Groove rifling, that and Marlin didn't exactly go over the top on that particular commerative.

Have you tried shooting a gas check bullet with black powder?

 

[shafter]

Wow, who counts the number of grooves in a BP revolver barrel? Someone is hooked pretty bad I suppose.

 

[[email protected]]

I have about a dozen guns I use in competition. I can tell you how many grooves there are in each one, the bore & groove dia. The rate of twist, and the angle of the crown. I guess I'm hooked.