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forestswin

forestswin

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finally got to the range with my new CE Prochrono Digital and tested some 45 acp rounds:D

and I didn't shoot it

I am looking for reference books, magazine articles etc that will help me understand what's going on and how to use this chrony for load development

here's the data
Gun: C*** GCNM
Cases: All New "IMI Match"
Primers: CCI 300
Bullet: Penn Bullets 200 grain SWCBB Target grade (14 BHN) (H&G 68)
Powder: 4.5 grains WST
OAL: 1.25" Crimp at 0.470"

10 shots (816, 805, 795, 784, 791, 780, 780, 794, 788, 795) f.p.s.
HI = 816 f.p.s.
Low = 780 fps
AVG = 793 fps
E.S = 36
Std Dev = 11

an interpolated velocity for a similar bullet in Lyman Cast 4th is 756 fps
Bob P. says this bullet is rated to go 850 to 900 fps
this combination shoots < 1" groups at 25ft to 45ft (I will need optics to go beyond that distance)

does this data say there is a need do anything different?

I also shot a bunch of 357 SWC's that had pretty high E.S. and Std Dev numbers, but they were all with cases that have been fired 5 or 6 times - still very accurate but nothing to report on them
 
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SD and ES numbers can be helpful. If a recipe produces a poor group but has low numbers, that suggests wind deflection, shooter error or something else influenced that group and the recipe deserves a reshoot. And if the group and the numbers suck, that often simply means it isn't going to work for you.

BUT having said all that, I have some rifle handload recipes that have not-so-good numbers but shoot one-hole 100-yard groups. So who knows? Just last week, I shot a .223REM load of a 52-grain Sierra MatchKing over 24.5 grains of Benchmark powder that clocked an average of 3,095fps with an SD of 32 and an ES of 64 but shot into a one-hole group just 0.156" larger than the bullet diameter. I also recently shot a one-hole group 0.222" larger than bullet diameter with a 6mmREM using a 69-grain Berger Varmint bullet over 43.0 grains of Varget. Contrary to the .223 load, it clocked 3,710fps but with great numbers - 6 and 11.

Oh well, the numbers make for interesting conversation. Beyond that, I don't put a whole lot of faith in them.

Ed
 
The chrono comes into it's own when testing long range target loads. At 600 to 1000 yards, a large velocity swing will show up on the target as vertical stringing. Plug some numbers into a ballistic callculator and see what the drop is for two different shots with a 100 fps spread. At 100 yards the average rifle round is going fast enough that even a wide velocity swing can still put them in a nice small group. For handgun use, the chrono simply confirms book load data. At handgun range the only thing important is how well they shoot. Actual velocity is just "nice to know" info.
 
Ed - thanks for the insight - I agree - for me target shooting, ultimately its just the size of the group on paper that matters.

Bluedot - I am somewhat "old school" - so getting permission is better than asking for forgiveness - THANKS

Fkimble - I am getting ready to start reloading for some long guns - and that was what justified getting the chrony for me. I can definitely understand the value for calculating external ballistics, but just hoping that it can help some for pistols at shorter ranges since I bought it and am going to chrony handgun test rounds anyway.

ADDITIONAL QUESTION????????
WHAT ARE VERY GOOD, GOOD, FAIR AND POOR EXTREME SPREAD AND STANDARD DEVIATION NUMBERS?
GOOD <20ES / 10 SD? percentages of average V?
 
Would have been a great 1st outing if the 816 fps did not show up................but that's the way things go.
Just when you think you found a good load a very low or high reading shows up to widen the ES spread but not to worry.

I have had lots of good groups with loads that had a high ES. These do not mean that the load is no good, just that something happened to get a wide reading. It could just be a muzzle down/up thing or how the powder ended up in the next case after recoil, weak case, different bullet weight or Dia..............not a big deal for just one test on a load.

I usually test a load 2-3 times before I give it a thumbs up or down. Weather, lighting, and if you are having an "Off" day all play a part in test groups and fps readings.

Enjoy your new toy !!
 
If you want to see how little speed differences can make at 25 yard pistol distances, load up some otherwise good loads with the same bullet that are 100 fps difference.

I've seen it done more than once with the result that the two loads made just one group on the target. In other words, most of the time a few fps difference in a handgun load makes NO practical difference.

When a few fps causes a large change, it usually means there is another problem. I found that making major power with a certain plated bullet in a Brn HP 40 resulted in patterns instead of groups, probably because the plating was being broken at the higher speed. At minor power, accuracy was excellent.
 
IMHO, as a handloader for more than 50 years, the addition of a chronograph really helps a long range rifle handloader. You will find that those high and low velocity readings come more from variations in neck tension than any other manageable factor. By the use of the chronograph while a benchrest competitor I proved to myself that the individual weighing of the powder charge was a waste of time as long as I was using a very good powder measure. The other place the chronograph is very valuable is in shotshell loading for trap and skeet.
There, one will be a much better trap or skeet shooter IF the shot charge is as constant in velocity as possible. IMHO you shouldn't get hung up on the ES and SD figures. I also had very accurate rifle loads develop with not so great numbers. Get and read everything you can to read anything that Dr. Ken Oehler ever wrote. He is the chronograph guru. Amazon.com is your friend, but Oehler Research is a very customer oriented company and approachable. ..... Big Cholla
 
I agree completely. But one thing to remember with most "hobby-grade" chronographs is that they are manufactured for single-projectile use. Accordingly, they clock only the leading pellet of a shot charge, not the mass of the shot charge like more costly units made for shotshell use. The manufacturer of my ProChrono chronographs suggests that 35fps should be deducted from the readings when clocking shotshell loads.

Ed
 
As usual, this thread drifted of in directions only vaguely related to your question.

Your data is perfectly normal results for handloaded handgun ammo. Data indicates that you did a good job in the loading room. I have chronoed factory ammo with wildly differing velocities out of a single box.

It's important to recognize that minor velocity variation will have absolutely no effect on accuracy at the distances you are shooting, especially with a big .45ACP semiwadcutter. Handgun groups need to be at 25 yds. to be meaningful at all.

The biggest factors in handgun accuracy are: 1) the shooter, and 2) the gun.

Enjoy yourself...have fun!
 
I've never used a Chronograph in 30+ years of reloading. For rifle rounds, I work a load until the bullet hits where I aim and the drop is minimal. A 300 yard target will let you know in a hurry if a load is good, with or without numbers. For pistols, I never load "for velocity" so a chrono is irrelevant.

For me it's kind of like a racecar. Knowing the speed doesn't matter as long as you come in first.
 
Nevada - yeah - no worry - I'm just going to have some fun with it
- in a previous thread - venomballistics posted "we measure case length,COL,bullet weight, charge weight, neck thickness, sometimes even case weight and primer flash hole size in pursuit of a result.
It only makes sense to actually measure, rather than guess at, the result"

that made good sense to me

OKFC05 - I've had that happen with 2400 in 357 loads - I varied the load from 11.4 grains to 13.2 grains - except for a few midway in that range - they all hit within a 1.5" group (overlaying the targets) I have a picture of it in this thread http://smith-wessonforum.com/reloading/312607-whats-up-2400-a.html post#23
I'm really looking forward to testing that load range again only with new cases and see how they chrony - I would expect that I'll at least get a 100 fps difference from 11.4 grains to 13.2 grains - but we'll see

Big Cholla - thanks for the info - I am proving the value of a very good measure to myself http://smith-wessonforum.com/reloading/318562-redding-powder-measure-unique.html
thanks for the Oehler reference that's what I'm looking for - I will definitely look him up as soon as I hop off this page.

Ed - shotshell reloading is right after casting on my list of things to get into

Bob - thanks - I was hoping to get some feedback on what the data shows for the loading techniques I've used. I do shoot other guns at 25 yards with red dots and 2x scopes. Its just that the front sight is blurry to me on guns with iron sights at 25 yards. I can see the target and rear sight fine. Looking to put a JPoint sight on the 45. And yes - it is enjoying

SMSgt - I hear what your saying - I don't disagree - but personally I've always had a curiosity to research, read and try to understand as much as I can about things I like to do. I do hear "you're thinking about it too much" often - but for me its fun. By the way - at the range - after testing loads - I almost always throw a bunch of clay pidgeons up on the hill and just blast away - and if I miss - no worry - I just shoot another round at it
 
When you get into 12 Ga. trap loads give me a ring.........
46 years of shooting and 39 years of reloading shotgun loads with lead, bismuth and steel.........X-Lite 7/8oz to 1 1/2oz magnums at 1330 fps in a 2 3/4 inch hull and..... steel at 1850 fps.
 
forestswin said:
SMSgt - I hear what your saying - I don't disagree - but personally I've always had a curiosity to research, read and try to understand as much as I can about things I like to do. I do hear "you're thinking about it too much" often - but for me its fun. By the way - at the range - after testing loads - I almost always throw a bunch of clay pidgeons up on the hill and just blast away - and if I miss - no worry - I just shoot another round at it
Click to expand...

It's a matter of why you reload, I suppose. If velocity is your goal, chrono. If accuracy is your goal, whether a load is 2800 FPS or 2900 FPS isn't as important as consistency. The consistency will show up as a tight group.
 
forestswin, I think your load looks acceptable.

I like to use the chronograph for developing loads. Load manuals vary greatly both between companies and through the years. The chronograph helps sort the differences. I think it is useful, too, when a load shows great variation in velocity even if the group is good. I do not like to see one or two rounds with greatly lower velocities.

Sometimes adding powder or changing primers will help stabilize the load resulting in more even velocities and good accuracy which in my mind makes a better load.

As stated above, it is a good tool to help verify your methods and data.

WILDPIG
 
forestwin, I use same load (4.5 WST under 200 gr Missouri) and got pretty much identical results averaging 780 fps out of 5" SR1911.
 
iouri said:
forestwin, I use same load (4.5 WST under 200 gr Missouri) and got pretty much identical results averaging 780 fps out of 5" SR1911.
Click to expand...

thanks iouri - that's really good to know - I was planning on taking my 22 pistol with CCI std vel bullets to the range each time with the chrony to use as a base and to see if I get consistent velocities before I start my test rounds. your data helps by giving me another confirmed benchmark
 
Nevada - I will - I just got a nice Franchi, and will probably be shooting clay pigeons in the fall - I'm sure I'll get tired of buying ammo and add a shotshell reloader to my bench - then I'll want to learn everything about that - but for now its on the list

SMSgt - I do load for accuracy and I do measure everything now - and I do go for consistency - as I said - its my nature - but as time goes on - I'll learn that somethings just aren't as important as others. I do appreciate your replies - kind of keeps me in the real world

WILDPIG - thanks for the (acceptable):D I think this chrony is going to help me with load development and tuning a load - it will probably help more when I start reloading for my rifles. It is nice to have a little bit more info after the bullet leaves the gun besides the holes in the target
 
To answer your question, yes you may want to change that 45 load. The power factor you have reached is only 158.6. If you play the USPSA game you will be scored as a minor score and lose points. I've been out of the game too long and understand the power factors have been reduced, but I think are still about 165. Power factor is bullet weight X Velocity divided by 1000. Your average was 793X200=158600 divided by 1000=158.6. I used to load 5.3 gr WST and made major power factor with no problem and it was comparable in accuracy to your load.
 
H Richard said:
To answer your question, yes you may want to change that 45 load. The power factor you have reached is only 158.6. If you play the USPSA game you will be scored as a minor score and lose points. I've been out of the game too long and understand the power factors have been reduced, but I think are still about 165. Power factor is bullet weight X Velocity divided by 1000. Your average was 793X200=158600 divided by 1000=158.6. I used to load 5.3 gr WST and made major power factor with no problem and it was comparable in accuracy to your load.
Click to expand...

no so far I don't compete against anyone but myself the previous outing - I give myself points by the target rings and I never lose points:D

I expected to have to increase the load to shoot at 50 yards - so I will work my way up with WST

do I remember correctly - do you shoot a Colt Gold Cup? I am looking for advice on springs
 
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