Chrony necessary for 45-70 out to 100 yards?

[huntinlever]

I had a Competition Electronics Prochrono back in 2015 and liked its help in developing a previous load for the guide gun. I am wondering how many depend on just incremental charges and group tightness to do their load developments, for the limited scope of hunting within 100-150 yards? In a quandary about whether to stay with the light-diffuser style chrony on a tripod v. something like the Magnetospeed sporter. Or nothing at all but range time.

Thoughts?

[NSB]

I have, and use a chronograph for some loads. For something like my 45-70s (I’ve had quite a few) I just shoot for my best groups at 100y. I’ve never had a problem getting a load that shoots well and every load I’ve ever used works well for dropping white tails. I have enough loading manuals around to know pretty much what ball park velocity I’m getting. Once in a while I chrono one out of curiosity and it’s pretty close. It’s just not that critical for this cartridge at these close distances.

[huntinlever]

I have, and use a chronograph for some loads. For something like my 45-70s (I’ve had quite a few) I just shoot for my best groups at 100y. I’ve never had a problem getting a load that shoots well and every load I’ve ever used works well for dropping white tails. I have enough loading manuals around to know pretty much what ball park velocity I’m getting. Once in a while I chrono one out of curiosity and it’s pretty close. It’s just not that critical for this cartridge at these close distances.

Perfect. Thanks, really helpful.

[Winger Ed.]

I use one sometimes.
But I found my readings were always so close to the published data, I don't bother with it much any more.

If I ever strayed off into uncharted waters, I'd use it a lot.
Staying under max loads by at least 10%--- usually more, I don't feel I'm in danger of shooting my eye out.

[BLAHUT]

I use my coronagraph for all my load developments. With my 45/70, 45/60 I stay at about 1200 FPS, so coronagraph tells me when/how....

[huntinlever]

I use my coronagraph for all my load developments. With my 45/70, 45/60 I stay at about 1200 FPS, so coronagraph tells me when/how....

Like Ed and NSB, my plan is to hover up or down load book ranges for 1300-1400 or so FPS, and so long as groups are acceptably tight, I felt I might be good to go. I enjoy knowing more precisely, but at this point I need to keep cash for components as they come up.

Do you have a barrel chronograph? I've forgotten. I am intrigued by the Magnetospeeder sport, but I've seen some people complain of slippage between shots. Still, have to say, I was always waiting for the shot where I'd destroy the Competition Prochrono....

[country gent]

I use mine mainly with Black powder loads. Watching the extreme spread and standard deviation helps find the sweet spot in compression. A 1 grn charge of BP dosnt make a big difference in velocity but does change compression. But in the end accuracy determines the load

[stubshaft]

I'll stick to my diffuser plate Chrony and/or Oehler 33. The cost of replacing my Chrono's can be better spent toward primers and primers.

[Winger Ed.]

Oehler 33.

I thought I was the only one still using one of those.

[dverna]

If you shoot five groups that average 1.5” at 100 yards, will it matter if your velocity is 1300 or 1400 fps?

[W.R.Buchanan]

On guns like this I am looking at the trajectory of the boolit being usable over 200 yards. Typically if I'm on at 100 yards It will need +6MOA at 150 and 6 more at 200.

When sussing out my .45-70 load I started out at 25 gr and went up in 2 gr increments until the recoil got objectionable. that was 35 gr so I backed off to 33 gr which I could shoot 50 of in one morning and not get hurt.

Then refine zero at 100 yds. and then recheck at 150 and 200. 9" low at 150 required +6 MOA and 12" low at 200 required another +6 MOA on the Lyman Receiver Sight.

Randy

[huntinlever]

Thanks for the input guys. To be honest based on a range trip a bit thrown as to where to go from here - probably spoiled by my IMR 4198 load from years ago that was hot, but really tight. Suspect I'll have to start around 28 grains 5744 and build up from there.

[BLAHUT]

Thanks for the input guys. To be honest based on a range trip a bit thrown as to where to go from here - probably spoiled by my IMR 4198 load from years ago that was hot, but really tight. Suspect I'll have to start around 28 grains 5744 and build up from there.

I use a magno coronagraph. My load in my guide gun is a 515 gr Lee flat point bullet in pure lead, over 27 grs of 5744 on top of a mag primer, very accurate in my gun. Depends on what you plan on using this load for ? This load for my guide gun was my bear load when fishing in Alaska.

[huntinlever]

I use a magno coronagraph. My load in my guide gun is a 515 gr Lee flat point bullet in pure lead, over 27 grs of 5744 on top of a mag primer, very accurate in my gun. Depends on what you plan on using this load for ? This load for my guide gun was my bear load when fishing in Alaska.

Thanks Blahut. That Magneto seems pretty awesome.

For my 405 grain, just whitetail deer really. And I am pretty sure I'll get another 46-425Q from Tom (sold my last one years ago) for elk, if not deer as well. Not looking for screaming velocity so anything 1300-1450 would be great to me, but really looking for accuracy - which happened to be as I approached 1700 fps with the 425 grain previously.

In terms of this new bullet and 5744 I think I need a re-do as today's over 26-30.0 grain 5744 was not too great. I might have just been lucky or because I was willing to work the 425 to near max with the IMR 4198, I was really pleased with both the chrono data (shoot-through, Competition Electronics) and the tight groups at the time.

[Milky Duck]

many a good load has been ruined by a chronograph....if its accurate LEAVE IT ALONE....

[stubshaft]

many a good load has been ruined by a chronograph....if its accurate LEAVE IT ALONE....

Amen, Brother, like looking at ballistic charts will create a super killer or watching people shooting gel will kill an animal deader. It is almost like the adage about fishing lures where the only thing they really catch is fisherman. The ONLY thing that Matters is ACCURACY!!! If you can't hit it, you can't kill it!

[georgerkahn]

I thought I was the only one still using one of those.

My first chrony was an Oehler -- do not recall its number -- but one shot through two pieces of PAPER which had printed-circuit conductors on each, and "Nixie tubes" -- vacuum tubes with dots which would light up -- to use a chart to then determine speed! (Have times changed -- I now have both a PACT Infrared, an Oehler 35P, and a LabRadar.)

I am, whenever I can, a chronograph user. I strive for an unextreme spread -- I desire most of my bullets to leave the muzzle (yes, a few feet distant as 'start') at as close to the same velocity as I might. I play close attention to published data in manuals, too. There's soooo much I do NOT know, albeit I've been putting cartridges together for 47 or so years -- too many variables -- I desire accuracy and SAFETY!
Using the chronographs may or may not really help (???) but they give me a warm & fuzzy feeling that my loads are good ones for both me and the firearm I'm using.
Since my right leg went from "bad" to "badder!" I picked up a LabRadar which surely seems to save steps, but frankly have not used it (yet!) enough times to give an evaluation of this product.
BUT -- again -- I consider the chrony as a most necessary part of my shooting sport! I have but a few rifles, many much older than me (>74), and I wish my "moderate loadings" to BE 'moderate' for the old actions. Germaine to post -- I have an OLLLLD .45-70 as well as a new one. Albeit neither is a Ruger -- I do, and chrony, all my .45-70 Government loads to be safe for the antique...
geo

[huntinlever]

Thanks for the perspective guys and they are good arguments and food for thought. Have to sit on this one as I see merits to both positions.

To those of you who use a magneto-style chrono, do you shoot for the chrony data first, pretty much ignoring the paper results (I've heard this style chrono can change barrel harmonics and so impacts the POI), then use what you find in the chrony data to start shooting groups?

[georgerkahn]

Thanks for the perspective guys and they are good arguments and food for thought. Have to sit on this one as I see merits to both positions.

To those of you who use a magneto-style chrono, do you shoot for the chrony data first, pretty much ignoring the paper results (I've heard this style chrono can change barrel harmonics and so impacts the POI), then use what you find in the chrony data to start shooting groups?

As I wrote, for me, the two major things I look for are velocities in a range not too out of whack which that is printed in Sierra, Hornady, Lee, wtc manuals for the load I'm duplicating; and, that the run I shoot are not too great in velocity spread. If the spread is too great -- subjective -- I reckon there's no way I'll get consistent, repeatable results on paper or Bambi . The #2 is, my not having pressure gauges, reckoning, too, that if my velocities are in same range as those in manuals, I (knock wood!) won't be blowing up my firearm, or hurting myself/others.
Perhaps germane, a few years back a ring one moved on barrel to reduce harmonics and "guarantee" significantly better performance was marketed and I had to have one! Frankly, it seemed to work for me -- set up for THAT day's range trip. But -- again for me -- maybe I was doing something wrong? -- NEXT range trip -- same ammo from same box using rifle cleaned, etc., exactly as before -- by golly, I'd have to start out anew.
Hence, MY thoughts include harmonics perhaps important for those endeavoring 10-ring shots at 1,000 yards. For me -- at my normal seventy-five yard target -- it does not seem to be a significant worry. (Then again, note this is both ME and MY firearms... for others it may very well have a factor. ???)
geo

[ascast]

FWIW - I only used on for long rang stuff, match shooting. Anything inside of 200 yards I cant see much benefit, certainly inside of 100.