CZ .300 WM barrel twist rate, no heavy bullets?

[fatelk]

A friend recently bought a new CZ rifle in .300 Win Mag. I don't remember the model, but it's a beautiful rifle. I know he paid a pretty penny for it.

He reloads and has a favorite load for his old rifle, using 180 gr. bullets. He worked and worked with it in the new CZ but couldn't get consistent accuracy at all. He likes long-range hunting and is a good shot. He said he finally called CZ, and they told him that his new rifle has too slow of a rifling twist to stabilize 180 gr bullets, and they couldn't guarantee accuracy with anything over 170 gr.!!

I've never heard of such a crazy thing. It's hard for me to imagine anyone making a .300 Win mag that won't shoot 180 gr. loads. He said he never would have bought it had he known that, but he'll get some 165's and see how they work.

 

[jmr40]

I checked CZ's website and they list the twist at 1:12. Everybody else shows 1:10 for the 300 mag. That certainly does seem odd and would explain it not shooting well.

 

[Jim Watson]

A 12 twist is plenty for a 180 gr bullet.
Berger says it is adequate for their long long 190 gr VLD.
The rifle is not accurate with 180s because it is not accurate with 180s and that is that.
Unless there is something grossly wrong, it is seldom possible to pick out just why a barrel "prefers" one bullet and not another.
Of course he might have a lemon that will not shoot ANYTHING accurately, but let's hope not and see what happens with other loads.

 

[fatelk]

Interesting. I wonder why they told him what they did? I'm curios how it does with 165's.

 

[jmr40]

A different brand of 180 gr bullets may work better, but the odds of 180's working in a 1:12 twist are less than the odds of them working in a 1:10 twist.

 

[NG VI]

Might just not like those particular bullets, not 180s in general.

He'll really have to try other options, especially since he likes hunting at longer range.

 

[Craigman]

I may be wrong, but in my understanding,twist rate and bullet weight has more to do with rifling contact to the bullet. The example where the Bergers are good to 190/1:12 may be that Bergers tend to be longer than other bullets(more wieght spread out longer making less side/rifling contact). Accubonds, I believe, have less contact to rifling. I would just try more types of bullets and maybe go to bullet mfg's websites and see what else is out there. It's too nice of a rifle to accept less than what you want/need.

 

[HOOfan_1]

According to CZ's site...the Kevlar stocked rifle has a 1:12 twist, while the walnut stocked rifle has a 1:10 twist

 

[fatelk]

According to CZ's site...the Kevlar stocked rifle has a 1:12 twist, while the walnut stocked rifle has a 1:10 twist

http://www.cz-usa.com/products/view/cz-ultimate-hunting-rifle/
You're right. I wonder why that would be? It sounds like he got some bad info from customer service on the phone. According to the web site his rifle indeed has 1:10 rifling, which should be fine for 180's. Of course the web site could be wrong.

From CZ:

The CZ Ultimate Hunting Rifle (UHR) is a new CZ 550 based rifle in .300 Winchester Magnum that comes in at 8 lbs, and includes a minute of angle accuracy guarantee to 600 yards By maintaining quality control standards unheard of in the industry, the Ultimate Hunting Rifle delivers a level of accuracy formerly only available from high-end custom rifle smiths.

I'm pretty sure that's his rifle, the one with the walnut stock. It's a real nice looking rifle. He lives a couple hours away and I don't get down that way often, otherwise I'd go to the range with him and help him find a good load. If he tries a few different bullets and loads with it and it still won't shoot straight, it's good to know it has a guarantee like that.

Thanks everyone for the help.

 

[Jim Watson]

If you want to KNOW the twist rate, you can measure it with a swivel handle cleaning rod and a tight patch. I put a little tape flag on the rod, make a start mark on the rod against some reference point on the gun, advance the rod until the flag goes around once, make another mark. The distance between the marks is the rifling pitch.
Knowing a number is not going to make it shoot more accurately with that pet load, though.

 

[Jim Watson]

I may be wrong, but in my understanding,twist rate and bullet weight has more to do with rifling contact to the bullet.

I believe you are. Wrong, that is.
Bullet stability depends largely on total projectile length vs spin rate.

The VLDs have the reputation of being finicky to load because of their short bearing surface, so much of the bullet length in the long nose and boattail.

 

[dprice3844444]

try the 168 grainers and 190 / 200 grainers and see how they shoot.every rifle is different

 

[PreMod70]

200 grainers work real good in 300's with a healthy load of IMR 4831.

 

[fatelk]

He's pretty unhappy with his rifle, to the point of wanting to spend $800 to have it rebarrelled. He's convinced that 165gr bullets have no knockdown power at long ranges so it's useless as-is.

Apparently he talked to more than one CZ rep, and they all told him that his rifle definitely has a 1:12 barrel, and that it will not shoot 180's accurately unless they were flat-base round nose bullets!?

Personally I would just try some 165's, but does anyone else think that it's a bit odd to sell a high-dollar rifle that won't shoot a common bullet weight for the caliber?

 

[HOOfan_1]

What is he hunting? 165 grain has plenty of knock down power...but if you can't shoot 180 grain or above, you might as well be using a .30-06.

As other have said...maybe he should try some other brands of bullets before he does anything drastic.

I've got a CZ .22-250 with a 1:14 twist, I've been told by some that it won't stabilize bullets over 50 grains. Well it is just as accurate with 55 grain bullets as it is with 45 grain bullets.

 

[fatelk]

Update: he dumped it at a loss and bought a Remington.

According to CZ's site...the Kevlar stocked rifle has a 1:12 twist, while the walnut stocked rifle has a 1:10 twist

He asked them about that and they looked and said that was a mistake, though I just checked and if it is a typo they haven't fixed it yet.

He tried some good 165's in it, and they wouldn't shoot that great either. CZ told him to send it in and they would take a look at it, but it would take a couple months at least. They said they do not make a .300 that will shoot 180's. He didn't want to mess around for months on end hoping spending money on shipping and hoping they would fix it, so he just dumped it.

Personally I think it's pretty lousy to sell a rifle with the wrong rifling for one of the most common bullet weights for the caliber without spelling it out clearly beforehand, especially while misrepresenting it on their website. It sounds like their accuracy guarantee isn't worth much either; mostly sales hype. Too bad; the rifle just looked and felt like a winner.

I still wonder what they are thinking- a .300 Win Mag that won't shoot 180's? Is it just me or does that seem crazy? Seems a little like selling a .45 that won't shoot 230's.

 

[GooseGestapo]

Sorry, but my B.S. detector is "pegged out".

I've got a .300RUM with the same twist. It shoots 150-200gr bullets equally well, given an equal quality of bullet. (ie: Sierra, Speer, Hornady, Berger, or Nosler).

I suspect the rifle either had a bad barrel or more likely an issue with the stock bedding. $800 to rebarrel what is essentially a M98 Mauser is a "sucker" price. I can do it with a "decent" barrel that will shoot ~2moa for $150.00.

Two months service turn-around is reasonable. CZ would have made it "good". I had a ArmsCo s/s 20ga Shotgun my wife gave me for our 25yr anniversary. I had to send it back to Armsco because it would "double" when you fired it, either barrel. CZ bought out/took over the distribution of the Turkish made shotgun's. After 9mos, I had my dealer contact CZ about the gun. They "had" the gun, but had "lost" who it belonged too. They couldn't fix it, so sent me a NEW gun....... including the "fitted" recoil pad (Pachmayer) that had been installed on the "old" gun.

In my opinion, CZ is a "stand up" company. They honored the warranty on a gun they didn't even build/import, but they did "buy the company".

Good service, even if it did take a year to get "my" gun back.
BTW, the replacement gun has even nicer wood and metal-fit than the original that a friend at the shop where my wife bought it, had gone through several to pick out the "best looking one".......

OTH; I wish your friend good-luck with his new Remington. From what I've been hearing about Rem's, he's likely to be in a bigger predicament with a Remington. Don't even begin to talk about Rem-lin's. (Marlin's since they were bought out by the "consortium").

 

[fatelk]

I suspect the rifle either had a bad barrel or more likely an issue with the stock bedding. $800 to rebarrel what is essentially a M98 Mauser is a "sucker" price. I can do it with a "decent" barrel that will shoot ~2moa for $150.00.

I suspected the same thing, especially since it wouldn't shoot well with 165's either. He said the best it would do was about 2moa, not acceptable for a $1400 rifle with a "guarantee" of 1moa.

To me, even 1moa is not that impressive. I have more than one $300 rifles that will do that any day of the week. If it was me, I would have found an old used Remington and had a reputable gunsmith put a high quality barrel on it.

I also thought the local gunsmith was trying to shaft him on the price of a barrel. He claimed that a top-of-the-line Pac-Nor barrel blank is $500, and the CZ has some odd-ball threads that take a lot of work to fit, so it would be $500 labor to install. He convinced him that $800 installed was a "great deal". That set off my "BS meter".

My complaint with CZ was that they told him the rifle was not designed to shoot 180's. True or not, that seems ridiculous to me in that caliber, especially since they don't say that in the advertising AND it's advertised as having a rate that will work for 180's.

Perhaps they could have easily fixed the barrel or bedding issue and it may have shot 165's and 180's fine, but they told him it wouldn't, tough luck.

 

[cmooresubmoa]

Late

I don't buy that from CZ, the barrel has to be bad or the scope if he did not buy the package deal.
I am an FFL holder and have bought 2 of the packages for buddies of mine and I have shot both of these with 1/2 moa (small clover) groups at 100 yds with factory ammo. I am speaking of the UHR package here not the tactical.
On another note that rifle was built and tested using 200grain DRT ammo which is what Alice Poluchova uses in her UHR that she hunts all over the world with. The package has the gun, Nightforce 5.5x20 scope, and case. It is an awesome package, the action and that fully adjustable single set trigger makes that gun shoot like that. I wish I would have seen this post earlier because I would have bought that gun from your buddy in a blink. I would love to know what the guy found that bought it from your buddy.