Let's talk muzzle velocity....

[jrebel]

So....I have been handloading for quite some time now and have never really paid that close attention to my muzzle volocity.  I was always hand loading for hunting purposes and based my final load off of accuracy. 

Well, a couple weeks ago, I finally broke down and bought a Magnetospeed V3 to see what my muzzle velocities are. 

This was the data with a 7 shots out of my .270 which, if I do my job, will shoot well under an inch groups. 

Shot #1  2681
Shot #2  2733
Shot #3  2694
Shot #4  2719
Shot #5  2712
Shot #6  2750
Shot #7  2751

SD 26.7
Max Spread 70 fps
Average 2720

My question is....is this acceptable or can I tighten it up a little?  What reccomendations would a person have to tighten this up without any major changes as the accuracy is there. 


My .308 is quite a bit better

Shot #1  2778
Shot #2  2807
Shot #3  2805
Shot #4  2772
Shot #5  2804
Shot #6  2776
Shot #7  2789

SD  15.1
Max Spread 35
Average 2790

[Duckslayer89]

So....I have been handloading for quite some time now and have never really paid that close attention to my muzzle volocity.  I was always hand loading for hunting purposes and based my final load off of accuracy. 

Well, a couple weeks ago, I finally broke down and bought a Magnetospeed V3 to see what my muzzle velocities are. 

This was the data with a 7 shots out of my .270 which, if I do my job, will shoot well under an inch groups. 

Shot #1  2681
Shot #2  2733
Shot #3  2694
Shot #4  2719
Shot #5  2712
Shot #6  2750
Shot #7  2751

SD 26.7
Max Spread 70 fps
Average 2720

My question is....is this acceptable or can I tighten it up a little?  What reccomendations would a person have to tighten this up without any major changes as the accuracy is there. 


My .308 is quite a bit better

Shot #1  2778
Shot #2  2807
Shot #3  2805
Shot #4  2772
Shot #5  2804
Shot #6  2776
Shot #7  2789

SD  15.1
Max Spread 35
Average 2790

My 308 only shot 2520 with a 165 grain bullet factory nosler trophy grade ammo 22 inch barrel

[JimmyHoffa]

You could get more precise in your loading, sometimes that can help get a closer spread.  Things like:  Weighing and sorting the bullets right out of box (for example the box of Hornady 200 gr that I have consists of bullets from 197 gr to about 202 gr).  Using all powder from one lot/container, or even trying to separate powder from within the container to get more similar grain sizes (like putting on the table near the tumbler--not on in right against; seems to work the larger grains up to the top).  Brass prep.  Etc.

So, with your shots--what was the sequence like?  Is first measured from cold/clean bore?  Approximate same temp of barrel for each shot?  A warmer cartridge gives higher pressure/velocity than a cooler identical one.

[Jason]

What are you using for a crimp die? I tightened up my velocity spread with the Lee factory crimp die.

[jrebel]

So....I have been handloading for quite some time now and have never really paid that close attention to my muzzle volocity.  I was always hand loading for hunting purposes and based my final load off of accuracy. 

Well, a couple weeks ago, I finally broke down and bought a Magnetospeed V3 to see what my muzzle velocities are. 

This was the data with a 7 shots out of my .270 which, if I do my job, will shoot well under an inch groups. 

Shot #1  2681
Shot #2  2733
Shot #3  2694
Shot #4  2719
Shot #5  2712
Shot #6  2750
Shot #7  2751

SD 26.7
Max Spread 70 fps
Average 2720

My question is....is this acceptable or can I tighten it up a little?  What reccomendations would a person have to tighten this up without any major changes as the accuracy is there. 


My .308 is quite a bit better

Shot #1  2778
Shot #2  2807
Shot #3  2805
Shot #4  2772
Shot #5  2804
Shot #6  2776
Shot #7  2789

SD  15.1
Max Spread 35
Average 2790

My 308 only shot 2520 with a 165 grain bullet factory nosler trophy grade ammo 22 inch barrel

This is a Kimber Mountain Ascent and it hated 165/168 grain bullets but loved the 150 grain accubonds.  It is quite the shooter....though I have to 100% due my job as it is such a light rifle.  If I mess up just a little it really is magnified in the results. 

[jrebel]

What are you using for a crimp die? I tightened up my velocity spread with the Lee factory crimp die.

I have never crimped my rifle bullets....maybe I should??  Does it make that big a difference? 

[jrebel]

You could get more precise in your loading, sometimes that can help get a closer spread.  Things like:  Weighing and sorting the bullets right out of box (for example the box of Hornady 200 gr that I have consists of bullets from 197 gr to about 202 gr).  Using all powder from one lot/container, or even trying to separate powder from within the container to get more similar grain sizes (like putting on the table near the tumbler--not on in right against; seems to work the larger grains up to the top).  Brass prep.  Etc.

So, with your shots--what was the sequence like?  Is first measured from cold/clean bore?  Approximate same temp of barrel for each shot?  A warmer cartridge gives higher pressure/velocity than a cooler identical one.

Shto sequence with the .270 was 3 shot (10 seconds between shots)....Waited for barrel to cool and then shot 4 with 10 seoconds between.  Was a little curious how the heated up barrel would react and I agree....appears the warmer barrel produced the highest volocities. 

The .308 is a super light barrel and heats up fast.  Did the same shot sequence to see if I could replicate the results and it didn't appear to effect it as much even though the barrel was heated up pretty good with the second shot volley. 

[Curly]

Must be 150 gr bullets in the 270.

H4831 or RL26 is probably where you want to be.

[jrebel]

Must be 150 gr bullets in the 270.

H4831 or RL26 is probably where you want to be.

Yes 150 grain partition being pushed by H4350.  Not sure changing powder is the way I want to go based on my accuracy.   Here is my 5 shot group (the flyer is my fault  )

[Duckslayer89]

So....I have been handloading for quite some time now and have never really paid that close attention to my muzzle volocity.  I was always hand loading for hunting purposes and based my final load off of accuracy. 

Well, a couple weeks ago, I finally broke down and bought a Magnetospeed V3 to see what my muzzle velocities are. 

This was the data with a 7 shots out of my .270 which, if I do my job, will shoot well under an inch groups. 

Shot #1  2681
Shot #2  2733
Shot #3  2694
Shot #4  2719
Shot #5  2712
Shot #6  2750
Shot #7  2751

SD 26.7
Max Spread 70 fps
Average 2720

My question is....is this acceptable or can I tighten it up a little?  What reccomendations would a person have to tighten this up without any major changes as the accuracy is there. 


My .308 is quite a bit better

Shot #1  2778
Shot #2  2807
Shot #3  2805
Shot #4  2772
Shot #5  2804
Shot #6  2776
Shot #7  2789

SD  15.1
Max Spread 35
Average 2790

My 308 only shot 2520 with a 165 grain bullet factory nosler trophy grade ammo 22 inch barrel

This is a Kimber Mountain Ascent and it hated 165/168 grain bullets but loved the 150 grain accubonds.  It is quite the shooter....though I have to 100% due my job as it is such a light rifle.  If I mess up just a little it really is magnified in the results.

That's what happens to me. If I mess up a tiny bit the bullet goes haywire. Frustrating. But off hand I took a shot at a steel target hit dead nuts where I was aiming. Sometimes I wonder if the bench messes me up.

[b23]

Do you keep track of how many times you reload a piece or brass?  In that seven shot string,  had every piece of brass been reloaded the same amount of times or were they a mix of different amounts of times they all had been loaded??

[jrebel]

Do you keep track of how many times you reload a piece or brass?  In that seven shot string,  had every piece of brass been reloaded the same amount of times or were they a mix of different amounts of times they all had been loaded??

Haven't kept track.....All are under three times reloaded with most being second time as they were mostly factory loaded rounds to begin with. 

[Magnum_Willys]

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

[jrebel]

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

[Magnum_Willys]

Ive wondered myself if rounds in mag were warming up but have never checked.  Just going from 50 to 75 degrees might explain some if they actually warm up?

[JimmyHoffa]

I don't know if being in the mag warms them up that much.  When you wait between shots to you leave the bolt open after the shot, then chamber right before the next shot or chamber immediately and then wait before the next shot?

[Blacklab]

1/2 inch moa @ hundred yards is great. If your thinking of trying longer ranges say 500 +. Then you need to bring your sd down as close to 10 or lower consistently. Case prep and bullet seating is of great importance. Measure your chamber length. Some rifles like long jumps some like short. You want your ogive as close to the lans without touching.   

[high country]

I'd aneal the necks and play with depth.  The spread is the killer if you shoot much beyond 5ish hundred.

Reloder 26 will take you over the 3 grand mark.....it did for me. I was shoving 130's at 2900 and now 150 LRAB @3k on the nose with single digit spreads.

[bobcat]

I'm getting 3100 feet per second with 140 grain Bergers and RL26. My previous load with H4831 and the same bullet was 2,850 fps. Probably will never use anything but RL26 for my 270 Win.

[bearpaw]

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

I've never crimped bullets either, I'm wondering if you found crimping to be more accurate?

[high country]

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

I've never crimped bullets either, I'm wondering if you found crimping to be more accurate?

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

I've never crimped bullets either, I'm wondering if you found crimping to be more accurate?

I struggled to get a known good shooting rifle to shoot a nosler lrab. After speaking with nosler tech it's a pretty common problem for that bullet with slow powders to have inconsistent dwell time in the throat.....Sometimes it glides through, sometimes it hangs for a moment and then takes off again after the case pressure builds.

Their advice was either find ways to increase the time between ignition and the bullet contacting the leade......more depth, crimp, hotter primers or faster powders.

I found that I can get that bullet to shoot well by using a faster powder. .....but I also took a 3" load down to .6" by seating deep and crimping.

While 99% of the time it's unnecessary to crimp a rifle load, there are times that it helps tremendously.

[wsmnut]

If you are going to start crimping I'd back off the powder charge and work up again.
I don't really see the necessity for it myself.
Barrel temp is likely what is affecting your speed.  It's hard to be patient when you are out at the range.  Bring two rifles and alternate shooting them.  Keeps one cooling and you shooting!
I have two .270's.  One likes H4831, the other likes H4350.  Your rifle clearly likes what you are doing.  And H4350 is one of Hodgdon's extreme line which is noted to be less temperature sensitive.
     Try your speed test again by going out to the range with an already fouled barrel.
You might find things settle down a bit.

Good Luck!

[rudysts]

There are two methods that I do to bring down extreme velocity spreads.

1 Control of your neck tension, this can be done with a full length bushing die or neck bushing die.
http://www.accurateshooter.com/technical-articles/reloading/neck-tension-not-just-bushing-size/

2 Testing different primers. I have found in my non magnum rifles that CCI BR2 or the 200s gave me best results along with Federal gold medal match 210s with the magnums CCI 250

By using this method I have been able to reduce my ES down in to the low 20s and in to the teens and some times single digits.
I think the more important number is your SD (standard deviation) this should be single digit. but if you only shoot short range high ES won't matter they will still shoot tight but it will show up at longer ranges 300 plus yards.

I never saw the need to crimp a bullet on a bolt rifle, much better to use a bushing die http://www.whiddengunworks.com/standard-reloading-dies/  I think these are the best dies out there they also come with a shoulder bump gauge.

[high country]

The lrab/slow powder combination is one that requires some nontraditional techniques. If you don't believe me, call nosler tech support and ask for yourself.

[jrebel]

Kind of interesting changes from my last trip.  I loaded a few more rounds with my newly cleaned trimmed brass (I changed cleaning methods from media tumbling to stainless steel), as well I let the barrel cool a little more between shots and my s/d went from mid 20's to 15.  I currently have more loaded with different primers....Some magnum and others just different brands.....I will see if I get these numbers even tighter.  Next I will work with seating depth though I think I have already found that sweet spot.  Updates to follow. 

[Blacklab]

That's great 

[jrebel]

OK....a good update after some tinkering. 

I reloaded a few rounds using different primers.  I was using Winghester LR primers for the original load.  This last load I used Federal Magnum Rifle primers and hands down had the most consistant velocities. 

5 Shot group...waiting 5-6 minutes between shots. 

Min:         2686
Max:        2701
Average:  2693
ES:          15
SD:          5.6

One thing I did notice...the magnum primers are flattening out.  They are not cratering and are not to concerning, but definitely appears to be highter pressures in causing flatter primers....at least compared to the LR primers.  Didn't get any better velocities though so I can't imagine the pressures are that much higher.     Anyone have any imput? 

[bobcat]

I know velocity isn't everything but I wouldn't be happy getting less velocity with a 270 than you're getting with your 308. Yes your accuracy is good but why not have both? Like I said before I'm using Reloder 26 and getting 3100 fps with 140 grain Bergers. Most of the time it will put three shots almost in the same hole at 100 yards. For many years I had used H4831 with 140 or 150 grain bullets and always got between 2800 and 2900 fps.

[jrebel]

I know velocity isn't everything but I wouldn't be happy getting less velocity with a 270 than you're getting with your 308. Yes your accuracy is good but why not have both? Like I said before I'm using Reloder 26 and getting 3100 fps with 140 grain Bergers. Most of the time it will put three shots almost in the same hole at 100 yards. For many years I had used H4831 with 140 or 150 grain bullets and always got between 2800 and 2900 fps.

I'm not sure less velocity with one caliber or another is reason to get me worked up.  I like that both rifles are ballistically similar, it makes switching between the two very easy.  I also don't shoot these guns beyond 400 yards so the difference in a couple hundred feet per second is negligable. 
I have tried to push the limits of speed with this set up and it just doesn't like it.  I have not tried other powders because I have so much H4350 and it has worked for so long.  I guess in short, It works...so haven't considered changing bullets or powders.  This combo has killed many of animal with excellent results. 

Maybe I need to buy another .270 so I can work up a speedy load.....don't give me any excused to own another rifle.   

[bobcat]

Well, there's something to be said for lower recoil loads too, I'd like your load for that reason, also the fact that it's easier on your barrel.

I'm loading my 338 Win Mag to only around 2,750 with 210 grain Partitions, and some may think that's too mild.

But that's the nice thing about handloading. You can tailor your loads to exactly what you want.

[Biggerhammer]

Go with the .270 WSM, the .270 Win is a anemic slouch.🙃

[high country]

Go with the .270 WSM, the .270 Win is a anemic slouch.🙃

Until reloder 26 is put into play.

[jrebel]

For argument sake, I ran the numbers between 2700 fps and 2900 fps....negligable to 400 yards, or am I missing something. 

[bobcat]

Try 2700 versus 3100. I think the biggest advantage is in reduced wind drift.

[jrebel]

Not sure I can get the 150 grain bullet to 3100.  Not data suggest I can even get close out of a 22" barrel. 

[high country]

Reloder 26 easily takes a 150 over 3k in 270win.

[Magnum_Willys]

Ive seen the magnum primers increase pressure and sometimes increase speed a lot or not at all depending on powder. I think they spike pressure initially and if there was unburnt powder with lesser primers then speed will go up. If all the powder was being used before the pressure will spike but drop off quicker so no speed increase. 

[Curly]

Here are the ballistic tables for 2700 fps and 3050 fps.  Wind speed was 10 mph.

[jrebel]

Well.....I bought a pound of Reloader 26 and worked up a few loads.  I haven't chrono'd them yet, but I did have a revelation.....my groups have tightened up with hotter loads.  This is different than any other powder I have worked with on this rifle.  60 grains of Rl 26 had the best groups.....though not as good as I would like, definitely workable.  I will work work a 60.5 for a max load next and see what happens then play with bullet seating depth. 

One thing I am not crazy about....These loads will surely burn the barrel out significan't quicker as it heats up very quickly. 

If I get a load that groups well, I will chrono them....I am sure they will be pushing 3K, which is very surprising to me. 

Updates to come.   

[bobcat]

Cool!   

I don't know if I mentioned my load before, but I used 61.2 grains with Berger 140 grain VLD's and got 3100 fps. This is with a Browning A bolt and 22 inch barrel.

[jrebel]

Well after multiple attempts and lots of tweeking, I cannot get rl26 to stabilize the 150 grain partitions.  Best groups I could produce were 1.5".  Being that I have started this journey and also that my other 6.5 creedmoor is shooting so well, I have decided to work with a few more loads.  Next will be 140 grain bullets (vld hunters and accubonds).  I will update as my progress goes for others that are looking accurate .270 loads.  Worst case scenario I go back to my 150 grain partitions at 2700 fps.   

[high country]

If they are not keyholing, stability isn't your problem. I'd be curious to know if your brass is anealed, and if you've tried big (.2") jumps. I bought 8lbs of 26 and fought it in my 270 until I understood that it builds pressure late so the ignition cycle is critical to get right. Consistent neck tension is paramount if the bullet cannot be jammed....ime.

[CP]

Well after multiple attempts and lots of tweeking, I cannot get rl26 to stabilize the 150 grain partitions.  Best groups I could produce were 1.5".  Being that I have started this journey and also that my other 6.5 creedmoor is shooting so well, I have decided to work with a few more loads.  Next will be 140 grain bullets (vld hunters and accubonds).  I will update as my progress goes for others that are looking accurate .270 loads.  Worst case scenario I go back to my 150 grain partitions at 2700 fps.   

1.5" is plenty accurate for a big game round.

[jrebel]

Forgot to get out of archive mode so didn't get the first chrono.  Here is a 5 shot group with 4 shot chrono using 51 grains H4350 and 140 grain burger VLD Hunting bullets.  I think this load is a keeper.  As for getting better velocities....well, my rifle just doesn't like speed, I guess. 

Series   12    Shots:   4
Min   2774    Max   2791
Avg   2781   S-D   7.9
ES    17      
         
Series   Shot   Speed      
12   1   2774    ft/s   
12   2   2785    ft/s   
12   3   2776    ft/s   
12   4   2791    ft/s   
----   ----   ----   ----

[Biggerhammer]

What barrel length? That's right on par with 7x57 velocities with the same weight bullet.

[jrebel]

What barrel length? That's right on par with 7x57 velocities with the same weight bullet.

22" barrel