Two different barrels and velocity differences in the .270 W

[Siskiyou]

Last summer I went to the range with two .270 Winchesters in tow.  One was a M700 Remington.  The other was a Savage 110.  I also had a Chrony with me.

Both rifles have 22-inch barrels.

The handloads were (1) 150 grain Hornaday pushed by H4831 and (2) 140 grain WW old style Silvertips pushed by WMR.  

After reviewing my records from that day I find that the velocity from the Savage with both loads is consistently 50 fps higher then the Remington.  Is this a normal variance between to rifle barrels?  I should note that there was no signs of excessive pressure in either rifle.

This has my curiosity up.  Is the barrel on the Savage better.  It has proven to be very accurate, but the Remington barrel provides good accuracy.  It may not be as accurate as the Savage barrel. It is hard to tell because I have fired the Savage many more rounds.  If I was to go on a long range antelope hunt which one would I take.  Most likely the Savage.  I have taken deer at over 250 yards with the Remington and the Savage, but what about a 400 yard shot?  I took a buck at close to 300 yards using a M760 in .270 Win. resting the rifle on my pack on top of a large boulder.

When the snow is melted I need to do some more shooting.  I need to try out another Remington with a 22-inch barrel and see what the difference is.  I do not think that the fps difference between the two rifles at velocity and energy levels produced by the .270 makes a difference at 400 yards and less.  

In general terms I sight my rifles to shoot 2.75 inches high at one hundred yards.

[jvs]

Is there a difference in twist between the two?

[Siskiyou]

jvs.  A good question, and something that did not come to mind.  I always thought both rifles have 1 in 10" twist.  A quick check of my Lyman Reloading Handbook 46 Edition shows that Remington 700 and Savage 110 have 1 in 10" twist.

Back in the late 50's era I would hear my Dad and his buddies discuss the merits of using the 1 in 12" twist in the .270 barrel.  I am sure this discussion was triggered by one of the gun writers of the period.  According to my source the "old "  270 Weatherby Magnum had a 1 in 12" twist.  The current models have a 1 in 10" twist barrel.  The 1 in 12" twist would make good sense for the guy who want to shoot rock chucks with 90/100 grain bullets and then switch to 130 grain bullets for deer.  A good option for the budget restricted shooter.

As a very budget restricted teenager I found my Rem. 760 in .270 Win. very effective on rock chucks, jack rabbits, and digger squirrels.  The 760 also has a 1 in 10" twist barrel.

Another interesting item on barrel twist from the handbook is that Husqvarna used a 1 in 9 1/2" twist.  Mannlicher-Schoenauer used a 1 in 9" twist.  My assumption is that Europeans followed the path of their 6.5 rounds that started out with long, heavy for caliber, round nose bullets.

 My assumption is these barrels would better stablize the 170 grain Speer, and 160 grain Nosler PT bullets.

[jvs]

50 fps isn't much, but it is a difference.  So I would check the headspace between the two.  A small amount of blow-back may be the reason.  Even a difference of powder lot numbers or primers could be the difference.

[nomosendero]

Siskiyou, this is not uncommon at all. The availability of inexpensive chronographs has been a real eye opener to shooters everwhere. It is a fact of life that there are fast barrels & slow barrels, even with 2 rifles that
are just alike. I see this alot because me & one of my brothers buy
the same cal.& model of rifle & work up a good load for both rifles when possible, sometimes we have to still develope a load for each rifle, as 1 rifle will like 1 load but not another. We have 2 identical 25-06's that had a vel. difference of 80fps with the same load & no there is nothing wrong with either rifle. I have heard of more difference than that with other rifles.

Some might assume that the faster barrel may be more accurate because
perhaps the bore is slicker, less burrs, etc. but this is not allways true. There are other factors such as the crown, how precise was the chamber cut, just too many factors to mention.

50FPS difference is not a big deal, especially since you are aware of it. Take the rifle that groups your desired hunting load the best & the one that
you can shoot the best from field positions, hopefully it will be the same
rifle.

[Siskiyou]

Powder, bullets, cases, and primers for each load are from matching lots.  

I have noticed over the years that the Savage 110 has a slightly tighter chamber then the M760 and M700.  This is only apparent with some reloads.  I have spent a lot of time loading favorite hunting loads for each rifle.  In the case of the 110 a favorite load is pushed by WW785 powder, 140 grain Hornaday boattail bullet.  They are lit off by Winchester large rifle primers.  I load this one in Remington Nickle cases to quickly identify the load.  This load is kept like a fine reserved wine.  This a very accurate load in the 110 and produces top velocity without pressure problems.  One of the reasons is that WW785 was discontinued some years ago.

I also have reserved loads for the M760.  They are pushed by H4831.  The bullet is the old 150 grain Norma Match boattail.  This bullet works great on deer, but I would not use it on heavier game.  I have found the jacket inside the hide on the far side a number of times.  The core has exited.

The M700 likes most anything I have run down the barrel.  The M760 did not like some WW 150 power points.  But the M700 loves them.  I bought three boxs of the same lot number on sale.  After taking a deer at long range with the M700 using the WW power points I set them aside for load of choice with that rifle.  I had planned on using them at the range and then reloading the brass.  The M700 barrel also likes Hornaday, and Remington 150 bullets along with 140 grain Silvertip bullets.

I purchased the rifles new and I am sure the head space is within factory specs.  But rifles very within the specs.  A case in point is that a younger brother had a Remington M760 in 270 Winchester.  I quickly found out that my hand loads lasted longer in my ammunition box then my factory loads. My cases would not chamber in his rifle.  I had just started reloading at the time and did not have a case trimmer.  Long necks could have been an issue.  I assure you that all my cases are trimmed to the proper length nowdays.

[jvs]

I suppose if you really need to know why this happens, a trip to a Bench Rest forum may be in store.  Having a difference in velocity of much less than .5% in different production rifles would have answers in such a place.  Those guys are even particular as to how deep the firing pin hits the primer on their rifles.  Of course, they have a tendency to put 5 shots in the same hole.  For them, one ragged hole means the barrel is shot out.   And for them 50 fps is a big deal.  

I can guess that a difference in production is probably the reason.  But there could be 20 different reasons.  That is why I asked you about lot numbers and primer make.

[Siskiyou]

I have a brother who is currently developing loads for a new 6.5-284.  I was not familar with the round and had to do a little research on it.  Found it is hot for those who shoot thousand yard matchs.  Something for everybody.

What generated the question in this case is two standard off the shelve deer rifles in .270 Winchester with the same length of barrel, shooting the same lots of ammunition.  One rifle a Savage 110 obtaining an average of 50 fps over the other rifle, a Remington 700.  This velocity difference is consistant with two different load combinations.  

Over the years the Savage 110 has gained a reputation of being accurate in a lower cost rifle.  I purchased mine in the later 60's and it has been a very good rifle.  I purchased the M700 ADL in 78/79.  It no longer looks like an ADL.  It now wears a mountain rifle stock.  Stocks and actions are glassed on both rifles.   The juices flow when guys compare there M700 or other brands against the Savage 110.  One or the other is saying their rifle is better.  I enjoy hunting with either rifle.

I ran the numbers using the 150 grain Hornady bullet in my Serria ballistic program.  Velocity was measure 15 feet from muzzle.  The difference in drop at 400 yards is .64" in favor of the Savage.  The difference in energy is 116 pounds in favor of the Savage.    I consider 400 yards an extreme range for me.  As I stated earlier the difference in energy at .270 levels at 400 yards is not major.  Is .64 inch in flatter trajectory critical at 400 yards.

[nomosendero]

Not hardly, knowing the range is the more important factor in bullet drop, as you can then plot the trajectory. Wind drift is the one to really watch,
trajectory is the far easier of the two to master, yet few discuss wind drift.

[Siskiyou]

nomosendero:  Times have changed with all the technology we have at hand.  But for years I have carried USGS maps while hunting.  Most of my hunting in canyon country.  I normally start at the top of the mountain and work my way down.  When possible I design my hunt so that I can watch the opposite side of a canyon or gulch.  On some of my favorite hunts I have set down with a topo map and measured the distance across the canyon.  Now days many people would use a range finder.  I use 400 yards as my stop point.  Normally shots will be from 100 to 250 yards.  I have stored these know distances between my ears.  Or I use the pointer in my gps to estimate the distance across a new canyon.

According to my Sierra Bullets infinity Exterior Ballistics Software the point blank range for the Savage 110 with the Hornady 140 gr. BTSP is 331 yards when sited in 2.75 inches high at 100 yards.  This is using a 8" vital zone.  This puts me 11.75 inches low at 400 yards.  I tape a data card on the stock of my rifle during hunting season.  I think I will try duct tape and magic marker.

The wind.  Many of the areas I hunt are oak with mixed conifer or mixed conifer.  Even the brush fields contain some conifer.  The conifer stands have taken a real hit from bark beetles.  There is a lot of standing dead timber around.  I normally pull out of the woods when ground level winds reach or exceed 10 mph hour.  When ground level winds hit 10 mph tree top winds are exceeding twenty miles per hour.  The real unknow is the wind velocity when shooting across a canyon and the path of your bullet is 300 foot above ground level at it's highest point.  The woods are dangerous and there is a lot of timber falling in some locations.  I hual a chain saw in the pickup to open up the road if a tree falls across it.  When the high winds get blowing it is better to back off and return on another day.

According to my data card wind drift at 400 yards with the 140 grain bullet is 10.53 inches and 10.18 inchs with the 150 grain bullet.  This is assuming a10 mph wind at 3 o'clock.  These numbers are interesting because is shows that velocity is not everything.  In this case the slower 150 grain bullet is least effected by the wind.  Food for thought.  

During hunting season or a day target practicing I carry a hand held anemometer in the pickup.  In most cases I have found that people over estimate wind velocity.  At the range I hang some surverying flagging to get a sense of what the wind is doing.

[nomosendero]

It sounds to me like you are the type of hunter that I enjoy hunting  with & it sounds like you are ready to me.

Good luck to ya!!  

[Siskiyou]

I have had a lot of years to learn and some good teachers.  I like the Scout Motto, "Be Prepared."  My tent camp is now in plastic tubs instead of cardboard boxes.  I even broke down one of the wood box.  I kept my dad's old pickup box.  It shows up in a lot of buck pictures from the pass.

I set a timer to get back to my reloading project.  Taking advantage of the winter weather to stock-up on practice and hunting ammo.  

I suspect we could have a good hunt.

I recently got the velocity bug.(Again, you would think I was twelve.)  Darn Chrony anyway.  At times one is better off not kowning. Does two more inches make a difference?  There are a lot of factors that come into play with off the shelf barrels.  I think both Remington and Savage produce a good barrel.  In two like barrels the 24 inch barrel should produce between 80 and 100 fps more then a 22 inch barrel.  Using a ballistic program that extra velocity makes the .270 Win perform as good or better then my 7MM Mag with it's twenty-four inch barrel.  The best performing bullets are Hornaday 140 boattail and their 150 softpoint.  Both are good deer bullets. Speer does not recommend it's standard 145 gr. 7MM bullet in the 7 Mag.  But it sure pops on the target end when fired from my rifle.

I planned on going to one of the bigger gun shows earlier this month but other circumstances got in the way.  One of the items I was going to look for was a new M700 24 inch take-off barrel.  The down side is that after buying a barrel and having it installed by a gunsmith I may not gain any thing for the bucks.  A positive side is that Remington, the defunked Winchester, and Weatherby Vanguard started producing .270's with 24-inch barrels.  


"Siskiyou, this is not uncommon at all. The availability of inexpensive chronographs has been a real eye opener to shooters everwhere. It is a fact of life that there are fast barrels & slow barrels, even with 2 rifles that
are just alike."

I agree with you.  I was disappointed when I ran both Winchester and Hornaday factory 150 grain ammuniton across my Chrony.  Neither made 2800 fps.  out of a 22-inch barrel.  But both worked great on deer.

Happy Days

 

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