Have a Rem 700 .243 Win rifle. Been using Hornady 105 Amax bullets to see how they shoot and have found that I get many flyers. Apparantly the 9.25 twist in my rifle with its' original 22" barrel is too slow. I have a new 26" barrel on it with the same twist...is it possble that a 4" longer barrel might be enough to stabilize this bullet---or am I only dreaming?
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105 Amax in a .243 Win
- Thread starter Wallyl
- Start date
Been using Hornady 105 Amax bullets to see how they shoot and have found that I get many flyers. Apparantly the 9.25 twist in my rifle with its' original 22" barrel is too slow.
Out of all the factors involved in making accurate rifles and ammo, why do you think your barrel's twist rate is THE problem??
If twist rate for the desired bullet is the problem, a longer barrel with the same twist won't change anything.
mxsailor803
New member
Have you tried other weights as well?
mxsailor803
New member
Wally, that’s kinda what I was suspecting. Twist is just wrong. About the max I’ve seen a .243win accurate with a 100gr. That’s also the Sierra ProHunters. For some reason, all of my .243’s (4 700’s and 1 788) like that bullet. I’m not complaining lol. Just means it makes my consumables easier to keep in stock lol.
@ Wallyl:
I used the Miller Gyroscopic stability factor formula (below) to check the twist, where
S = gyroscopic stability factor (dimensionless)
W = bullet weight (grains)
T = twist (inches per turn)
L = bullet length (inches), for plastic tipped bullets, ignore length of plastic tip
D = bullet diameter (inches)
S= [30*W*D(exp2)] / {(T)exp2*L*[(D)exp2 +(L)exp2]}
"S" should be between 1.3 and 2.0. Best range is between 1.4 and 1.7.
The formula is not as daunting as it looks. I couldn't figure out how to do superscripts, and so (T)exp2 means T squared. I used a bullet length of 1.06 inches for the 105 grain A-max and calculated an "S" of 1.73 for your parameters. So, the 105 A-max should stabilize. But these things are never precise and every gun is different.
During my fifty years of shooting, I've had at least six .243's come and go, and still have two more in the safe. It seemed like none of them did their best with bullets in the 100 to 105 grain range. For deer hunting, I used a 95 grain nosler partition, and it worked fine. I hear, a lot, that the .243 Win is inherently accurate, but I never found that to be the case. Each rifle was bug hole accurate with one specific bullet weight and one particular powder, but it was never the same from rifle to rifle. I spent a lot of different powders and different bullets trying to fine that magic load, and it got frustrating pretty quickly.
@mxsailor: I noted that you have a remington 788. Of all the .243's I've owned, my 788 was the most accurate. Unfortunately, it got stolen about 40 years ago.
I used the Miller Gyroscopic stability factor formula (below) to check the twist, where
S = gyroscopic stability factor (dimensionless)
W = bullet weight (grains)
T = twist (inches per turn)
L = bullet length (inches), for plastic tipped bullets, ignore length of plastic tip
D = bullet diameter (inches)
S= [30*W*D(exp2)] / {(T)exp2*L*[(D)exp2 +(L)exp2]}
"S" should be between 1.3 and 2.0. Best range is between 1.4 and 1.7.
The formula is not as daunting as it looks. I couldn't figure out how to do superscripts, and so (T)exp2 means T squared. I used a bullet length of 1.06 inches for the 105 grain A-max and calculated an "S" of 1.73 for your parameters. So, the 105 A-max should stabilize. But these things are never precise and every gun is different.
During my fifty years of shooting, I've had at least six .243's come and go, and still have two more in the safe. It seemed like none of them did their best with bullets in the 100 to 105 grain range. For deer hunting, I used a 95 grain nosler partition, and it worked fine. I hear, a lot, that the .243 Win is inherently accurate, but I never found that to be the case. Each rifle was bug hole accurate with one specific bullet weight and one particular powder, but it was never the same from rifle to rifle. I spent a lot of different powders and different bullets trying to fine that magic load, and it got frustrating pretty quickly.
@mxsailor: I noted that you have a remington 788. Of all the .243's I've owned, my 788 was the most accurate. Unfortunately, it got stolen about 40 years ago.
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Twist is just wrong.
I look at it the opposite way. The rifle isn't wrong, the bullet is wrong, for that rifle.
So long as you don't make a rush to judgement. IT could very well be other factors or a combination of other factors that make a given bullet unsuitable.
it can even be the shooter's personal expectations. Take the .244 Remington for one example.
"...Apparently the 9.25 twist..." Is just fine. Mind you, Remington uses a 1 in 9.125" twist. That being the normal, 'standard', twist for the .243.
It's not about the barrel length. It's about the quality of the barrel and the load. Along with the trigger and the rest of the rifle. You will see an increase in velocity, but not a lot.
A Rem M700 is a hunting rifle. An AMax is a match bullet. Hunting rifles may or may not shoot match bullets well.
Is the thing bedded? The trigger been done? Lotta variables involved.
Did you work up the load? Been using Speer 105 SP's(absolutely not a match bullet. Does astounding things to ground hogs though.) out of a 9.125 rifle for eons, with IMR4350.
It's not about the barrel length. It's about the quality of the barrel and the load. Along with the trigger and the rest of the rifle. You will see an increase in velocity, but not a lot.
A Rem M700 is a hunting rifle. An AMax is a match bullet. Hunting rifles may or may not shoot match bullets well.
Is the thing bedded? The trigger been done? Lotta variables involved.
Did you work up the load? Been using Speer 105 SP's(absolutely not a match bullet. Does astounding things to ground hogs though.) out of a 9.125 rifle for eons, with IMR4350.
A lot of people used to shoot the 105 A-Max out of factory twist Remingtons, air density will play a factor in if they stabalize or not. A cold day at sea level you may not have a fast enough twist in a Remington to stabalize the bullet. A 1:8 twist would be better if you live at lower elevations.Wallyl said:Have a Rem 700 .243 Win rifle. Been using Hornady 105 Amax bullets to see how they shoot and have found that I get many flyers. Apparantly the 9.25 twist in my rifle with its' original 22" barrel is too slow. I have a new 26" barrel on it with the same twist...is it possble that a 4" longer barrel might be enough to stabilize this bullet---or am I only dreaming?
It also could be your technique when shooting that's throwing the flyers. Practice makes perfect, so try to do everything the same way every time. I wouldn't go making changes to the rifle until you rule yourself out as much as you can.
There also could be an issue with your load. Is it a flyer or a keyhole? Keyhole strikes are a sign of bullet instability, flyers are usually something else. If it is a flyer it is more than likely an issue in your load development. You'll need to check your load over a chronograph and check your SD and ES, if it's large you need to try different powders, powder charges, primers, and seating depths to find what your rifle likes.
If you don't have extreme ES and SD, then check your ammunition for runout. Roll it across a small mirror and check bullet tips for wobble or get a concentricity gage from Hornady, Sinclair, RCBS, or ect. Straight ammunition shoots straighter to put it simply. Decapping your brass in a separate step and removing your expander ball from your sizing die greatly helps to reduce runout.
If you can't get the A-Max to shoot don't worry about it, Hornady discontinued the 105 A-Max for the A-Tip and ELD-X & M bullets. However, the 105 HPBT by Hornady is a great bullet that should 100% stabilize in you your current barrel. Plus Hornady is still making that bullet for the foreseeable future.
Not even close the SAAMI Standard twist for the .243 Win is 1:10" twist. Remington and a few others use faster than SAAMI twist barrels in the .243 rifles.T. O'Heir said:Mind you, Remington uses a 1 in 9.125" twist. That being the normal, 'standard', twist for the .243.
False, you don't need a "match" barrel to shoot match bullets. A quality bullet should absolutely be easier to find a load for than one that the QC is less on Rem CL and Win PP bullets come to mind, even in a lowly hunting rifle barrel.T. O'Heir said:A Rem M700 is a hunting rifle. An AMax is a match bullet. Hunting rifles may or may not shoot match bullets well.
You must have a lifetime supply of that bullet as Speer has discontinued that bullet probably close to 10 years ago. It was a good bullet, but it is nearly impossible to find in any quantity anymore. The flat base semi spitzer bullet flew like the proverbial "brick" you like to reference so much, but it did stabilize in 1:10 SAAMI spec barrels.T. O'Heir said:Been using Speer 105 SP's(absolutely not a match bullet. Does astounding things to ground hogs though.) out of a 9.125 rifle for eons, with IMR4350.
mikejonestkd
New member
WallyL, give them a try in your new barrel. It may or may not work well, but, until you try it you'll never know
I have 5 .243 win barrels, and all are 1 in 10. I get great results with 95 gr bullets, and decent groups with 100 gr Hornady BTSP. I have not tried your weight, since my rifles are just for hunting and shorter range target work.
I have 5 .243 win barrels, and all are 1 in 10. I get great results with 95 gr bullets, and decent groups with 100 gr Hornady BTSP. I have not tried your weight, since my rifles are just for hunting and shorter range target work.
Remington and a few others use faster than SAAMI twist barrels in the .243 rifles.
Anybody have any ideas why Remington went to a 1 in 9" or now, apparently 9.25"??
My personal theory is basically, "to make damn sure"...
Remington (again) badly misjudged the market with their .244 twist rate.
Gun writers were touting the .243 Winchester as a dual purpose rifle, good for varmints and deer. Winchester's .243s had a 1-10" twist, which did acceptably well with both lighter bullets and the 100/105gr "deer" bullets of the day.
Remington put a 1-12" twist in their .244 Rem, apparently with the thought it would be used as a varmint gun. The slower twist didn't stabilize "deer" bullets well, and the buying public was being told they wanted a dual purpose rifle and the .244 wasn't good at that. After the first year (or maybe 2) Remington changed the twist rate to 1 in 9", but the public had already made up their minds.
Later, when Remington "repurposed" the .244 into the 6mm Remington, they had a 1 in 9" twist. Sales improved some, but its was never going to catch the .243 in popularity.
T O'Heir
It is a stock rifle...no bedding or trigger work. The barrel is a 26" target barrel made by Remington. I worked up the load I am using a powder Chg of 41.0 grains of AA 3100 w/CCI-200 primers.
My thanks to all others that have responded...will try it out again early next week.
It is a stock rifle...no bedding or trigger work. The barrel is a 26" target barrel made by Remington. I worked up the load I am using a powder Chg of 41.0 grains of AA 3100 w/CCI-200 primers.
My thanks to all others that have responded...will try it out again early next week.
bamaranger
New member
.243
For sometime I was a .243 basher and did not believe it was a reliable deer cartridge. I was repeating the lines many of my elders spoke in my youth, all were .30 cal and heavy bullet believers. My Dad strayed from the faith a bit, bought a .243 as a varminter, shot it well, and began to kill deer with it too. Accordingly, when Dad's .243 came my way, I hunted it a bit for nostalgia, and bamaboy killed several with it as well. I say all that to lead up that I have worked with the .243 a bit in the last 10 yrs or so and noticed some trends in my two rifles. Dad's is an early Savage 110 with docked barrel at 21" and the other a Mossberg 800M carbine with a 20" tube.
Both shoot 100 grain slugs with hunting accuracy, the Savage a bit better than the Mossy. The rather rare Mossberg 800M will shoot bugholes with lighter 85 grain bullets, the Savage responds as well, but not so dramatically. The jury is still out on my confidence level with the lighter bullets on deer, but hit right, they get dead, no exits wounds yet.
Speer's not made that 105 gr RN that O'HEIR mentions, in ages!
For sometime I was a .243 basher and did not believe it was a reliable deer cartridge. I was repeating the lines many of my elders spoke in my youth, all were .30 cal and heavy bullet believers. My Dad strayed from the faith a bit, bought a .243 as a varminter, shot it well, and began to kill deer with it too. Accordingly, when Dad's .243 came my way, I hunted it a bit for nostalgia, and bamaboy killed several with it as well. I say all that to lead up that I have worked with the .243 a bit in the last 10 yrs or so and noticed some trends in my two rifles. Dad's is an early Savage 110 with docked barrel at 21" and the other a Mossberg 800M carbine with a 20" tube.
Both shoot 100 grain slugs with hunting accuracy, the Savage a bit better than the Mossy. The rather rare Mossberg 800M will shoot bugholes with lighter 85 grain bullets, the Savage responds as well, but not so dramatically. The jury is still out on my confidence level with the lighter bullets on deer, but hit right, they get dead, no exits wounds yet.
Speer's not made that 105 gr RN that O'HEIR mentions, in ages!
Wally,
My wife used to have a Rossi R243 that absolutely loved Hornady 105gr Match bullets over a charge of RL26. Twist was 1:10, so was slower than yours.
Hornady told me in no uncertain terms that the 105 would NOT stabilize in a 1:10. But had no issues with it out to 500 yards. (Furthest we got to shoot it before trading on another rifle).
My wife used to have a Rossi R243 that absolutely loved Hornady 105gr Match bullets over a charge of RL26. Twist was 1:10, so was slower than yours.
Hornady told me in no uncertain terms that the 105 would NOT stabilize in a 1:10. But had no issues with it out to 500 yards. (Furthest we got to shoot it before trading on another rifle).
reynolds357
New member
I hate the AMax personally. Quite often they appear at the gun club with a "free" sticky note on the box.Out of all the factors involved in making accurate rifles and ammo, why do you think your barrel's twist rate is THE problem??
If twist rate for the desired bullet is the problem, a longer barrel with the same twist won't change anything.
Having said that, 4" will definitely affect stability of a marginally stable bullet. Velocity stabilizes bullets by spinning them faster. You can stabilize bullets in a 1-10 22-250 that you have to be 1-8 in a .223 to stabilize.
I have shot Sierra 107s out of a Savage Model 14 Sporter. Believe from memory it also has a 9-1/4 twist. According to Sierra, 9-1/4 isn't fast enough for the 107s, but I guess my rifle didn't get the memo. Dings a 10" plate at 500 yards five out of fives times, all the time. At one time, I won enough bets with that rifle and load to buy lunch. Sadly, no one will bet me any more.