Optimal rifle twist for .260 Remington with heavy bullets

[MichaelEber]

If all goes well and the bills do not overwhelm me then I hope to get my rifle rechambered next month.
Obviously I chose the .260 Remington and plan on using either the 140 VLD or the 149. For the heavy bullets what is the optimal twist? 1:8 is planned but I'm wondering of 1:8.5 or 1:9 is better. And if I get a good deal on lighter hunting bullets to load will I overtwist them with the higher twist rate?

 

[Huskydriver]

1 in 7.5 if your using 140+ bullets.

 

[308pirate]

There is no optimal, as long as what you use is sufficient. 1 in 8 is more than sufficient for the bullets you plan to use.

 

[surgeon260]

1:8 is the slowest twist I would consider, and that is ideal for 140 grain and under. If you want to shoot the new super heavy 6.5s, I would go 7.5 or 7.

A couple things to think about:

Are you running a short action, and do you want to load from a magazine? If yes, the best bullets are going to be in the 130-140 class. Anything heavier/longer (like the Sierra 150 or Berger 156) and you will be shoving the bullets pretty deep in the case in order to fit in the magazine and feed reliably. I would also argue that the 260 case capacity is not ideal for the super heavy 6.5 bullets. You will lose a lot of velocity with the 150/156 and they will only have a ballistic advantage way out there. If you plan on shooting, say, 800 yards max then the 130/140 class bullets are the ticket.

 

[308pirate]

And if I get a good deal on lighter hunting bullets to load will I overtwist them with the higher twist rate?

A 1 in 7.5 or 1 in 7 should not damage big game bullets, but they will probably blow up varmint bullets.

I used to blow up 95 gr Hornady Vmaxes on a regular basis when I tried them for the 200 yard stage of the NRA regional match course. I used to compete with a Win M70 in 260 Rem with a 1 in 8 Krieger. 123 Scenars worked just fine tho.

And the point about the super heavy bullets is one that I missed. If you plan on feeding from the mag with those long ass bullets, the 260 Rem is not what you want. The bullets will be ridiculously deep in the case. 6.5 Creedmoor or maybe that new 6.5 PRC would serve you better for mag feeding.

 

[MichaelEber]

No plans for super heavy bullets. I am looking at 140 and at most I think it is a 147(?) bullet. Nothing heavier and leaning heavily with the 140.

 

[308pirate]

1 in 8 will be fine and 1 in 7 won't hurt nothing

 

[XLR308]

The 1-8 twist would serve you well for the 130 and 140 class of bullets and if you don't run into mag length problems many are doing well with a 1--8 and the 147eldm.
I went with a 1-7.5 Bartlien for my 65 creedmoor but was primarily interested in the 147eldm and 150smk from the start but should have no compromise if I run the lighter 130 grain pills either.

 

[Hiker12]

Not sure why one would run bullets heavier than 142gn in a 260 Rem do to velocity drop. Been shooting 260 Rem for 4 years with great success using the following.
Bartlien barrel 28" with break
1:8 twist
(handloads ) with .005" jam
123gn Amax , H4350 45gr powder MV 3,003 fps
140gn Sierra, H4350 42.7gr powder MV 2,865 fps
142gn Sierra, H4350 42.7gr powder MV 2,855 fps
Use 142 load for 1000yard shoots with great success. So to answer the gentleman's question in regards to twist 1:8 would be my pick every time. In my opinion it is not worth the sacrifice of velocity to shoot the heavier bullets.( If you were to only shoot 140gn or higher) then would go to 1:7 twist. Also keep in mind your free bore space for heavier and or hybrid bullets.

 

[NewsShooter]

Not sure why one would run bullets heavier than 142gn in a 260 Rem do to velocity drop. Been shooting 260 Rem for 4 years with great success using the following.
Bartlien barrel 28" with break
1:8 twist
(handloads ) with .005" jam
123gn Amax , H4350 45gr powder MV 3,003 fps
140gn Sierra, H4350 42.7gr powder MV 2,865 fps
142gn Sierra, H4350 42.7gr powder MV 2,855 fps
Use 142 load for 1000yard shoots with great success. So to answer the gentleman's question in regards to twist 1:8 would be my pick every time. In my opinion it is not worth the sacrifice of velocity to shoot the heavier bullets.( If you were to only shoot 140gn or higher) then would go to 1:7 twist. Also keep in mind your free bore space for heavier and or hybrid bullets.

Look up the 147 BC, I was shooting them at 2830, no pressure issues.

 

[Hiker12]

Look up the 147 BC, I was shooting them at 2830, no pressure issues.

Will take a look just out of curiosity. But with every cartridge has a optimal bullet weight that is just right. But like everyone including myself we try to push beyond its peek performance. That's not to say it don't work, it's just the that optimal performance that we chase . By chance what are you using for a load for the 147gn and do you use a jump or jam when seating. I like to jam .005"- .010" will increase pressure and velocity.

 

[Supersubes]

Will take a look just out of curiosity. But with every cartridge has a optimal bullet weight that is just right. But like everyone including myself we try to push beyond its peek performance. That's not to say it don't work, it's just the that optimal performance that we chase . By chance what are you using for a load for the 147gn and do you use a jump or jam when seating. I like to jam .005"- .010" will increase pressure and velocity.

Quite a few of us have been shooting 147’s in creedmoors using reloder 26. My 23” Broughton launches them at 2850, with no pressure. I can’t get enough in the case to use a 140 with that powder. Some are reporting over 2900. Pretty exceptional performance.

 

[XLR308]

Not sure why one would run bullets heavier than 142gn in a 260 Rem do to velocity drop. Been shooting 260 Rem for 4 years with great success using the following.
Bartlien barrel 28" with break
1:8 twist
(handloads ) with .005" jam
123gn Amax , H4350 45gr powder MV 3,003 fps
140gn Sierra, H4350 42.7gr powder MV 2,865 fps
142gn Sierra, H4350 42.7gr powder MV 2,855 fps
Use 142 load for 1000yard shoots with great success. So to answer the gentleman's question in regards to twist 1:8 would bre my pick every time. In my opinion it is not worth the sacrifice of velocity to shoot the heavier bullets.( If you were to only shoot 140gn or higher) then would go to 1:7 twist. Also keep in mind your free bore space for heavier and or hybrid bullets.

The primary reason I went with a 1-7.5 twist was to use the 147 and 150 grain bullets, the secondary reason is I wanted no longer than a 23" finished length on my barrel to keep it more compact and balance out better.

I know i could have squeezed a bit more performance out of it going to 26" but in reality it's still just a 65 creedmoor I didn't feel that hotrodding the little case for miniscule gains would have outweighed my preference for better balance and OAL.

I am allready considering a 65 PRC or 6.5-284 For that purpose to be used for hunting.

 

[MichaelEber]

My interest in the ELD 147 is it has the highest BC I've seen: close to .7!

 

[XLR308]

My interest in the ELD 147 is it has the highest BC I've seen: close to .7!

You should also take a peak at the 150smk and Berger is coming out with a 156 grain and I believe JLK is supposed to be releasing a 147 as well.

 

[Triple D]

Running 142’s and 150 SMK’s in two 260’s at 1000ft above sea level with 26” 1:8’s. I was afraid I was going to need a slightly faster twist, but it’s done great. My load with the 150’s is a tenth of a grain lighter than my 142 load with both jumping 18 thou.

Running 130 bergers, 140/147 eld-m and 142 smk’s in my 22” 1:8 twist 6.5creed gas gun.

I’d say 1:8 is the minimum if you’re wanting to shoot the heavies, and 1:7.5 or 1:7 if you want to get the maximum BC.

 

[Niles Coyote]

I have a few 6.5's with 1:8 barrels, no issues maintaining accuracy at distance nor have i seen BC's less than what hornady says I should see with the 147 eld in predicted drop verses actual drop. But if your wanting to try the 150 matchking I'd go with a 1:7.5 as that bullet is longer and can't cheat a little like the polymer tipped eld can.

 

[NewsShooter]

Will take a look just out of curiosity. But with every cartridge has a optimal bullet weight that is just right. But like everyone including myself we try to push beyond its peek performance. That's not to say it don't work, it's just the that optimal performance that we chase . By chance what are you using for a load for the 147gn and do you use a jump or jam when seating. I like to jam .005"- .010" will increase pressure and velocity.

42.6 of RL-16, hornady brass, jumping 20 thou, I don't jam and the eld's seem to like a jump, as much as 50. I shoot in all conditions, heat, cold, rain, etc, jamming them just seems like a unnecessary pressure risk. I got them near 2900 but started showing extractor marks, though bolt lift was fine and no popped primers. This node was slower but less pressure and accurate.

 

[Hiker12]

The primary reason I went with a 1-7.5 twist was to use the 147 and 150 grain bullets, the secondary reason is I wanted no longer than a 23" finished length on my barrel to keep it more compact and balance out better.

I know i could have squeezed a bit more performance out of it going to 26" but in reality it's still just a 65 creedmoor I didn't feel that hotrodding the little case for miniscule gains would have outweighed my preference for better balance and OAL.

I am allready considering a 65 PRC or 6.5-284 For that purpose to be used for hunting.

The 1: 7.5 twist is a good choice for the larger bullets. Have shot a 6.5x284 before at a benchrest match before and liked it a lot . Its a nice round bit more punch than a 260 rem. It is a barrel burner about 1500 rounds you get out of it. If you benchrest shoot should last awhile. But tactical shooter and use it as a primary shooter wont last as long. I shoot every weekend so went with the 260 Rem. Don't know much about the other round you mentioned 65 PRC ? Overall 6.5mm is a great bullet

 

[Hiker12]

Quite a few of us have been shooting 147’s in creedmoors using reloder 26. My 23” Broughton launches them at 2850, with no pressure. I can’t get enough in the case to use a 140 with that powder. Some are reporting over 2900. Pretty exceptional performance.

If reloading try a drop tube will help stack the grains of powder in the case. It opens up more case volume I hate to say youtube it but it is there and explains much brtter than I can.

 

[spife7980]

If reloading try a drop tube will help stack the grains of powder in the case. It opens up more case volume I hate to say youtube it but it is there and explains much brtter than I can.

 

[Niles Coyote]

I may have to make myself a 3 foot drop tube, LOL

 

[Supersubes]

If reloading try a drop tube will help stack the grains of powder in the case. It opens up more case volume I hate to say youtube it but it is there and explains much brtter than I can.

My drop tube is 24” long. I could add more but I’d just be crunching more during bullet seating, and I’m just not interested.

 

[MichaelEber]

The 1-8 twist would serve you well for the 130 and 140 class of bullets and if you don't run into mag length problems many are doing well with a 1--8 and the 147eldm.
I went with a 1-7.5 Bartlien for my 65 creedmoor but was primarily interested in the 147eldm and 150smk from the start but should have no compromise if I run the lighter 130 grain pills either.

I checked bullet lengths and everything from 130 to the 147 ELD are the same length. It isn't until you go bigger that a long action is required.
So the 140 and 147 ELD are my two target loads with the 140 should I go hunting.

 

[Hiker12]

Go Good example

 

[300ATT]

Inhav been shooting the 147 ELD with R26 in the .260 and have seen really good results. Speed is 75-100 fps faster than 140’s with H4350. Accuracy is decent and there is a noticeable difference in how well this combo bucks the wind over say the 139 scenars.

 

[Frank Green]

For up to 147gr. bullets a 1-8 will work but you will most likely be giving up some B.C. on the bullets.

According to my calc's the 150SMK need a 1-7.52 min. twist at CM velocities. If it was my gun and I was going to run mostly heavy bullets I'd go with a 1-7.5 twist.

All the bolt gun barrels in 6.5mm we've made SF have been 1-7 twist.

For testing purposes on my 6.5CM we made a 1-6.75 twist barrel. With 147 and 150gr. bullets I'm getting an honest 2700fps. Barrel length is 23" and the gun is a laser beam so far. Only shot it out to 430 yards but I have no complaints on either bullet.

Later, Frank
Bartlein Barrels

 

[1snowcat]

I know its an old thread but if I shoot 130-140 grain pills (260 Rem) is a 8.5:1 twist too slow? reason I ask is I have the barrel but it hasnt been chambered yet...

 

[Supersubes]

I know its an old thread but if I shoot 130-140 grain pills (260 Rem) is a 8.5:1 twist too slow? reason I ask is I have the barrel but it hasnt been chambered yet...

Measure your bullet lengths and run the math for stability. Berger or JBM have calculators.

 

[Bhobbs]

I know it’s an old thread but if I shoot 130-140 grain pills (260 Rem) is a 8.5:1 twist too slow? reason I ask is I have the barrel but it hasnt been chambered yet...

According to Berger, their 140 VLD would be marginally stable with the 8.5 twist. Their 130 VLD would be stable.

 

[Lost_Phil]

For the love of Jove, use the free Berger Twist Rate Calculator, it will work with any bullet.

The two biggest things that will play a major role in the twist rate needed besides the bullets weight, is Temperature and Elevation.

The 144 LR Hybrid at 15F/Sea Level...

The same 144 LR Hybrid at 15F/1000FT....

You need to see what your lowest temp is going to be and what elevation you will be.

Added: Most twist Rates given by bullet and Ammo manufactures are generally the minim need to make it stable at room temp at sea level.

 

[M4orturnate]

Not sure why one would run bullets heavier than 142gn in a 260 Rem do to velocity drop. Been shooting 260 Rem for 4 years with great success using the following.
Bartlien barrel 28" with break
1:8 twist
(handloads ) with .005" jam
123gn Amax , H4350 45gr powder MV 3,003 fps
140gn Sierra, H4350 42.7gr powder MV 2,865 fps
142gn Sierra, H4350 42.7gr powder MV 2,855 fps
Use 142 load for 1000yard shoots with great success. So to answer the gentleman's question in regards to twist 1:8 would be my pick every time. In my opinion it is not worth the sacrifice of velocity to shoot the heavier bullets.( If you were to only shoot 140gn or higher) then would go to 1:7 twist. Also keep in mind your free bore space for heavier and or hybrid bullets.

Depends what you want to do. Lots of guys run the 153 and 156s between 2600 and 2700 so you can watch the flight. Wind call would be pretty much the same as what youre shooting

 

[1snowcat]

For the love of Jove, use the free Berger Twist Rate Calculator, it will work with any bullet.

The two biggest things that will play a major role in the twist rate needed besides the bullets weight, is Temperature and Elevation.

The 144 LR Hybrid at 15F/Sea Level...
View attachment 8302826

The same 144 LR Hybrid at 15F/1000FT....
View attachment 8302827
You need to see what your lowest temp is going to be and what elevation you will be.

Added: Most twist Rates given by bullet and Ammo manufactures are generally the minim need to make it stable at room temp at sea level.

Wow,
We have crazy differences in the table due to 8.5 twist , and my elevation of 7500ft...
shows much more stable...