What is the std rate of twist for it,if there is such a thing. Need to know before I send my out to be redone.
til later
Sako & Tikka use 1:16
CZ = 1:9.5 or 1:10
Krieger & L barrel makers say 1:12 or 1:14
1:12 is good, and I think 1:10 is better
Spot
That's my concern! The twist rate for this thing seems to be all over the place. I'm thinking 1-10 or 1-12 also. Maybe some others will chime in. Guess I'll start me a poll on my note pad and see where I end up. Thanks,Spot!!
til later
Some CZ's are 1:14 like mine, measured. Given a choice I would have probably said 1:10, but my 9.3X62 shoots fine. 1:16 seems a little slow to me, the Scandinavians seem to prefer rifling a little on the slow side, but I like their rifles and they seem to shoot well.
I miss quoted.
Sako & Tikka 9.3 twist rates are 1:14
Remington uses 1:16 for the whelen but the custom makers recommend 1:12 or 1:14..
Ken Waters in his 9.3X62 Pet Loads article (Handloader #155 Jan.-Feb. 1992) states his Husqvarna has a 1:16 twist but shot accurately. My Husqvarna 30-06's have 1:12 rifling as opposed to the 1:10 norm.
No problem Spot! In general you weren't wrong as I have seen reload data with twist rates topping out as high as 1-16.
THANKS Husqvarna! I'll put you down as 1-10 on my poll here. Weatherby did there early thirty cals. in 1-12 or 1-12.5 I believe,for some reason.
til later
As near as I can tell the original twist in the 9.3 x 62 from Germany was around 1 in 14.
I don't know what the optimum twist is. But if I was building a 9.3 I would likely go with a 1 in 12 just to make sure it stabilized some of the very modern long heavy bullets such as the 9.3 300 grain Swift A frame.
Something to also consider is. It seems like back in the early 80s I remember reading the US military conducted tests with the 5.56 in the M16 with various twist rates. And concluded the a slightly fast twist rate helped out on penetration tests. It could have been in NRA publications I read this.
That test would kinda make sense as the bullet would be stabilized more and would maybe help keep it on a straighter track when penetrating. THANKS for the input! OK,that's a vote for 1-12. I'm bettin 1-10 or 1-12 is gonna be right and that's so close it won't matter.
til later
Blaser does the 9.3 at 1-14 out of a 22" barrel. I don't have that barrel, but have heard it is extremely accurate. I would probably copy that.
Coop
Jon Speed's Original Oberndorf Sporting Rifles reproduces a table of cartridge specifications from the Mauser factory c.1925 that shows the 9.3X62 twist as 360 mm (14.17" converted to English measure). A-Square used this twist in their barrel for the loads they developed to match CIP ballistics.
The .375 H&H standard twist is 12".
jim
EZEARL, I found this site. It may help.
http://stevespages.com/page8e.htm
The twist rate is determined by the LENGTH of the bullet and to a lesser extent the velocity...a heavier LONGER bullet needs a faster twist than a shorter bullet.
You need to determine what bullets you want to use, determine the bullet length then pick a twist that will stabilize it.
For the most part, the normal rates most rifle makers use are good ones to pick. If you are undecided about which bullet you want to use and might go with lighter bullets over heavier ones then a twist in the slower range, 16-18 range will work. If going with the heavier bullets then 10-14 range will work. I wouldn't go with a twist outside normality for anything except special target or varminting work, there are too many problems that can arise from doing things of this nature.
For the 9.3 cal at normal velocity ranges for all normal weights...250 to 320 gr...and 2100 to 2600 f/s...any twist from 14 to 19 will stabilize for normal hunting usage.
I'm building a 9.3x62 right now using a Lothar Walthar 24" #720 barrel, 1-14.2 twist. It will stabilize all the bullet weights I plan to use...mostly on the heavy side...286 to 320...but will also work with the lighter but longer 250gr Barnes TSX BT's if I decide to try them, and any weight RN or cast lead RN's I want to try.
As always...the rifle will determine what bullet it likes after you start load development as far as the highest accuracy is concerned.
For hunting accuracy...5 into <2"...any normally available for the caliber twist will do.
'Njoy
My Husqvarna is 1:16 and stabilzes 286 gr bullets just fine.
My old pre-war Model 70 has a 1:14 Bauska barrel on it, and doesn't shoot any better than the Husqvarna.
Ted
Blaser does the 9.3 at 1-14 out of a 22" barrel. I don't have that barrel, but have heard it is extremely accurate. I would probably copy that.
I have two Blaser 9.3x62 barrels, and both are one hole groupers with every load that I have tried.
Dave,GREAT site,THANK YA!! I've got some 270gr Speers coming any day now. I'll use the formula and see what it says.
Did a good bit of reading and rereading the past few days and it seems I was over the left field wall on this 1-10 to 1-12 twist guess. 1-14(or its metric equivelent)seems to be the norm in the factory rifles and most custom rifles. Speer #12 uses a custom Rem 700 at 1-10 but the next cartridge is the 9.3x74R in a Valmet 412S at 1-14. Maybe the 9.3's are VERY forgiving with twist rates. 1-10 to 1-16,anyone know of another caliber that runs with a twist rate variation that wide?
Really APPRECIATING all the info/suggestions too!!
til later
EZEARL, did you get the PM I sent yesterday? The reason I ask I posted something yesterday and it didn't go through. Dave
Ed Plummer of AHR recommended a 1-14 twist for my 9,3x62mm build. Said it would handle the 250gr. TSX on up through the 320gr. Woodleighs.
Yea FO,that pretty much confirms it,THANKS! I'm hearing from ALOT of people with 1-14 9.3's. Just as soon as I get the Speer 270grs in I ordered I'm going to try the Greenhill Formula that Dave sent me just for the heck of it. I figure 20"or 21"bbl w/1-14 is how I'm going. THANKS again!
til later
While looking at twist rates for 9.3x62 I found this old thread. I was concerned about the twist rate that Lothar Walter has in their 9.3 barrels (1:14,2) but this is the standard twist that CZ has in their rifles and when I used a twist calculator I found that 1:14.2 would stabilize the longest bullets I could find data for (320 grain Woodleigh) with ease. I guess the factories actually got this one right- unlike all the stupid 1:14 22-250 barrels out there!
My Sauer 202 has 14" twist and it shoots every bullet from 232-325 gr. in one hole !
My CZ550FS in 9.3 has right at a 1 in 9.5" twist rate on a 20 inch barrel. shoots the 250tsx into nice little cloverleafs.
That makes no sense at all why would they speed the twist up like that when a 1-14" will stabilize virtually any bullet made?
While looking at twist rates for 9.3x62 I found this old thread. I was concerned about the twist rate that Lothar Walter has in their 9.3 barrels (1:14,2) but this is the standard twist that CZ has in their rifles and when I used a twist calculator I found that 1:14.2 would stabilize the longest bullets I could find data for (320 grain Woodleigh) with ease. I guess the factories actually got this one right- unlike all the stupid 1:14 22-250 barrels out there!
I totally agree about the CZ factory getting it right. Along with proper glass bedding, my rifle shoots lights out:
After it was dialed in on the bull, I fired 10 more downrange:
The 286gr. partition is also a freight train on critters. It just keeps going and going:
I like the 9.3x62 so well that I've thought about having JES rebore my classic sporter 30-06 to one. I wonder what twist rate they use? Anyone know???
JES uses 1-14, and they shoot very well with 250s and 286s.
Thanks buddy. One of these days I'm going to pull the trigger on that. I really like the 9.3x62mm. To me, it seems very versatile and extremely capable.
Your welcome. I must say I should not have waited as long as I did, could have used one of them years ago.
You know what's funny, I was looking for a good 375H&H when my 9.3x62 fell into my lap. I was at a local freelance gun rag writers house and he was showing me some of his beautiful rifles. I was mainly looking at his pre 64 model 70's and the question came up about dangerous game guns and 375's. He said he has something "almost as good. It's been to Africa and has some dangerous game under it's belt". I asked what it was and he said, "you may have never heard of it before, but it is a wonderful 9.3x62mm". "There is a problem with it though". I asked what?? It looks like a very nice rifle. He said, "It thinks it's a damn varmint rifle
..., It makes my 222 look bad". I said that doesn't sound like a problem to me
. Overall, I am extremely happy with my 9.3x62mm. I did, however, feel as if it was a little overkill on the cow elk I posted a picture of earlier. I know that bullet kept going and going
.
Overkill is hard to accomplish, you failed in your overkill efforts with that elk! Likely you could nearly eat right up to the hole.
The 9.3x62 is a wonderful gun to have hunting deer here in Alaska where you might have a 200 yard shot an a buck or get in a fight with a brown bear at 10 yards. I really like the same spectrum of abilities the .375 has in an '06 sized gun with a six round capacity.
Amen buddy. Everything you just said is true..