What is the difference between micro groove rifling and ballard rifling??

Microgroove has more grooves but they are half as deep as Ballard type. That means that for cast bullets the hardness and bullet diameter are more critical to obtain good accuracy.Too few people knew this so Marlin dropped the microgroove from production !!

How can you tell me it is micro rifling or ballard rifling?

Micro groove lands are a few thousandths of an inch thick where as ballard cut is a conventional rifling, the lands are between 1/8" to 3/16" thick. IMHO, good riddens to micro groove rifling. As far as the big bore, they typically use ballrd cut as it can withstand the higher pressures generated by the big boys...

John

The whole point to the "Micro-groove" rifling was that it distorted the bullet jacket less and theoretically atleast
would aid gas sealing and accuracy.

The rub is that it didn't anticipate the rennisance
of cast bullet useage.

If you are shooting a 35Rem or 30-30 with jacketed bullets
a Micro-groove is fine, if not preferable.

My 1972 Marlin 1895 has ballard rifling but perversely I don't shoot CB's in it.
My brother's pre-safety 444S has the Microgroove tube, but
he also shoots jacketed bullets only.

AllanD

I've had a Marlin 1895 with the microgroove barrel for 28 years.

It handles "the higher pressures generated by the big boys" just fine and will shoot cast bullets just fine if they are sized .001" to .002" over groove diameter and are gas checked if driven over 1600 fps. When I was younger I could shoot the Gould hollow points into 2" at 100 yards with open sights!

Ya gotta wonder where some of this stuff comes from.

I believe it was Pope who made his barrels in "microgroove type" rifling back in the 19th century. His rifles were superbly accurate.

quote:

Originally posted by mete:
Microgroove has more grooves but they are half as deep as Ballard type. That means that for cast bullets the hardness and bullet diameter are more critical to obtain good accuracy.Too few people knew this so Marlin dropped the microgroove from production !!

Actually many of Marlin's 336 series still feature micro grooves.

quote:

Originally posted by Neverflinch:
Actually many of Marlin's 336 series still feature micro grooves.

Interesting to me, is that in one year (1979) at least some of the Remington 700-V rifles in .308 Winchester also came from the factory with Micro-groove barrels. Of course, they weren't called that.



To answer the question of how to tell if a rifle is Micro-groove or not, one of the easiest ways is possibly to count the number of grooves. Most large production factory made barrels have about 4-6 grooves. Most Micro-groove barrels appear to have 10-12 (or maybe more) grooves. At least that's true with the ones I've seen....

If I were looking for a 336 in 30-30 I'd specifically want a microgroove.

Why? Because the 30-30 is no more suited to cast bullet shooting today than it was in 1894 when the cartridge was introduced.

while I'm SURE that someone out there with careful casting and alloy selection is making a 30-30work I think a
32Win-Spl would be easier to make work well with them...

AllanD

Do any of you know when Marlin came out with the "Micro grooved" rifle? Just wondering when it was introduced.

1956 or so.