M77V TWIST RATE

[PebblePimp]

I just picked up '77 M77V (that's a pretty cool date) in .22-250. I cannot find a definitive answer on the rifle twist. It's all original. I have, at least, found out it's most likely a 1-14" or a 1-12". I'm thinking the former. Can somebody help me out? I've searched the net & old posts on here. I'm just stuck.

 

[rugerjunkie]

Only one way to know for sure...run the cleaning rod thruough it and measure how far it goes to make one revolution.

 

[GRAMPS 51]

I know my M77s in 222 rem and my 220 swift are both 1 in 14 so im pretty sure yours would be also but use the cleaning rod to make sure
And welcome to the forum :) :)

Gramps

 

[PebblePimp]

Thanks, guys. It's getting delivered to me tomorrow, so I'll have to wait a day. I have a CZ in .223 with a 1-12" twist. I'm fixing to start reloading & was hoping to luck out that both would love the same bullet weight as I gain experience. I'll post some pictures when I go put her through the paces.

 

[GRAMPS 51]

Generally the 223 will have a faster twist because they like 55gr plus bullets they need the faster twist to stabilize the heavier bullets

Gramps

 

[gtxmonte]

A factory barrel should have a 14 or a 12 twist. That's plenty fast for the type bullets you should be loading in that round

 

[PebblePimp]

Oh yeah. I'm probably going to run 50 gr. in my CZ. It's 1-12". It's perfect for a walking varmint/small game rifle.

 

[gtxmonte]

A hot loaded 22-250, with a 50-55 grain spritzer, is a deadly accurate varmint HAMMER out to around 300 yards. It doesn't need anything heavier. Of course it will shoot further, but to 300 or so, it is an absolute terror.

Haven't shot mine in a while, but only because I have plenty of other stuff I am messing with at the moment

 

[PebblePimp]

I'm figuring 45-50 gr. will be what I go with. Might try some 40 gr. too, just to see how they like it. A guy at the bow & gun shop with a newer 1-9" CZ .223 had 3 small clovers, 1 figure 8, & 1 well under a dime with 55 gr. loads he was working on. That suggests to take a few grains off my loads (theoretically).

 

[PebblePimp]

OK, the M77V in .22-250 is definitely 1-14". Like I said, I was pretty sure, but not certain.

 

[PebblePimp]

Finally got my photobucket account back up (haven't used it since MySpace), so here's a couple of pictures.

 

[dfletcher]

I have a few 22-250 varmint rifles. If someone could explain to me the "wisdom" of using a 1 in 12" or 1 in 14" twist, precluding the (about) +62 grain bullets, I'd like to be enlightened. I know making 50 to 55 grains accurately go alot faster than can be had in 223 sized cases is worthwhile, but can't that still be accomplished with a 1 in 10", maybe 1 in 9" rate?

 

[PebblePimp]

Slower twist will stabilize lighter bullets better, and they get more velocity than heavier bullets. You're giving up mass for speed.

 

[6GUNSONLY]

Slower twist will stabilize lighter bullets better

Well, not really, or at least not necessarily. The only real downside to the faster twist is higher RPM of the bullet (light bullet with short bearing surface + fast twist = higher rotational speed of the bullet in the barrel and in flight). This could theoretically result in the bullet being more prone to coming apart on impact or even (again, theoretically) in flight. A slower twist MAY shoot lighter bullets more accurately than a faster-than-necessary twist, but not necessarily. I have three fast twist rifles in .223 (a 1:7, and 1:8, and a 1:9). All of them shoot the lighter bullets very well (as light as the 36 grain Barnes Varmint Grenade).

As to the "wisdom" of the slower twist rates like 1:12 or 1:14, some of these twist rates were kinda standardized many years ago when 55 or maybe 60 grain bullets in .224 diameter were about as heavy as there were available. 40 to 55 grain bullets were the norm and those twist rates were fast enough for those weight bullets. A lot of older .22-250s had a 1:14 twist rate. Some of the older "heavy" bullets in .224 diameter were a semi-pointed design for this reason - shorter profile/ogive was more likely to stabilize well in the twist rates that were standard at the time (an example is the old 63 grain Sierra Semi-pointed - still a very good bullet that has given great accuracy for me).