all my reloads are slow

[42769vette]

every time i chrono my reloads on my ced m2 chrono my loads are always slower than what everyone else says there sameload does and slower than my books say itshould be going. for instance

7mm rem mag i just show with 60gr of h4931. 24 inch barrel 83degree temp

mine did 2537, hodgen says it should do 2787 but does notlist there barrel length

 

[bohem]

Re: all my reloads are slow

If you tell Hodgdon's website to print the data it will summarize it to a PDF format you can print directly to a printer.

Before you print it, the data summary will show you the barrel length.

 

[Fred_C_Dobbs]

Re: all my reloads are slow

250 fps seems more than the normal gun-to-gun variance. Especially since that 83° should give you a little boost.

I had a Shooting Chrony with the opposite problem ...everything was too fast. In that instance, it was the chrono.

Have you checked other rifles with this same chrono? Or other loads/charge weights with this same rifle? If so, did they look okay?

Are you by chance using an Eveready SHD battery? It's one of the few brand name non-Alkaline 9v batteries on the market. I found it made a difference in mine.

 

[223ai]

Re: all my reloads are slow

I don't trust my chronograph much, but it gives me a good starting point. Try taking the rifle to 200, 300, etc. to verify the FPS reading.

 

[KIDGLOCK]

Re: all my reloads are slow

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RJ Hunter</div><div class="ubbcode-body">Try shooting down hill. </div></div>

Or in a Vacuum .


Speed is not always the cure.

 

[vman]

Re: all my reloads are slow

Double check that you are shooting in the correct position thru bother sensors.

Ive had my chrony measure 2930fps, and then I moved the chrony slightly and it started measuring 2820fps on the same loads!

 

[42769vette]

Re: all my reloads are slow

mabye chrono position is my problem. i try and shoot 6-7inchess direct center above the sencors.

 

[TXTransplant]

Re: all my reloads are slow

Yeah my shooting chrony (cheap one) was registering as much as a 5% difference depending on where I shot the round relative to the chronograph upright pin things or whatever. I can't remember whether it was shooting high or low that was faster or slower, though.

 

[sobrbiker883]

Re: all my reloads are slow

I played with my hanloads trying to tweak my loads because I could never get good ES/SD numbers out of loads that shot great from my Chrony Gamma.

Shot a couple of loads over the local SO's Oehler and the two calibers I had on hand had SD's of 07 and 13 (latter were thrown loads).

I sold my Chrony setup within a week.

 

[pjparker]

Re: all my reloads are slow

1. Make sure you've got a fresh battery. My Oehler 35P is real sensitive to having a fresh Battery.

2. Check it against another chronograph, or work backwards. Shoot at distance and see if your actual drop agrees with what your calculated drop would be from your chrono data.

3. You may just have a slow barrel.

4. Pull the trigger harder.

 

[427Cobra]

Re: all my reloads are slow

427 to 427, I went out today with my new CED M2, my loads were going slow too, I discovered that you must tighten both sensors to the stick, what happens is they vibrate ever so slightly, causing them move apart, moving apart screws up the timing so slower speeds are recorded, once I discovered this my readings went way up, and SD and ES went into the single digits.

 

[Unsichtbar]

Re: all my reloads are slow

I shot through CED screens from prone and had to angle the screens to hit the target which was elevated. Readings were all off, just the change in angle increased the hypotenuse and gave low readings.

 

[427Cobra]

Re: all my reloads are slow

The bullet should pass thru parallel to the sensors, if not the timing will be off, this is reguardless of chrono used

 

[Deisel]

Re: all my reloads are slow

Amen 427Cobra. I managed to learn this the hard way which is how I seem to learn most things

 

[RTH1800]

Re: all my reloads are slow

You do not state what bullet you are using, but I do not think 4895 is a good powder for any of the 7 mag loads. You should look at H 4831, IMR 7828, which was developed for the 7 Rem mag. and others of that class. I like the 7mm Rem mag, but never could get velocities that justifyed the change from the 270 Win. For example, I can SAFLEY get 3250 out of a 130 Barnes TS in a 26" 270 Win and could only get 3050 out of a 150 BTS out of any of my 7mm Rems. I ended up going to the 375 H&H necked to 7mm with the 25 degree shoulder and get 3400 out of the 150 NP. generally I still prefer the 270 Win for most hunting, and I have shot quite a few elk, moose and grizzley with both. Just prefer the lighter rifle. Like both though.

 

[42769vette]

Re: all my reloads are slow

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">427 to 427, I went out today with my new CED M2, my loads were going slow too, I discovered that you must tighten both sensors to the stick, what happens is they vibrate ever so slightly, causing them move apart, moving apart screws up the timing so slower speeds are recorded, once I discovered this my readings went way up, and SD and ES went into the single digits. </div></div>

i bet i dont have the sensors on tight. basically EVERY reload ive done through it ive thought should have been faster.

for instance i shoot a 260 with a 142smk and 44 gr powder out of a 28 inch barrel and my chrono tells me that is 2750. with the drop data i cant remember what it acted like but it was close to 2800fps

 

[42769vette]

Re: all my reloads are slow

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rth1800</div><div class="ubbcode-body">You do not state what bullet you are using, but I do not think 4895 is a good powder for any of the 7 mag loads. You should look at H 4831, IMR 7828, which was developed for the 7 Rem mag. and others of that class. I like the 7mm Rem mag, but never could get velocities that justifyed the change from the 270 Win. For example, I can SAFLEY get 3250 out of a 130 Barnes TS in a 26" 270 Win and could only get 3050 out of a 150 BTS out of any of my 7mm Rems. I ended up going to the 375 H&H necked to 7mm with the 25 degree shoulder and get 3400 out of the 150 NP. generally I still prefer the 270 Win for most hunting, and I have shot quite a few elk, moose and grizzley with both. Just prefer the lighter rifle. Like both though. </div></div>

im using h4831. ive made that same typo on a couple forums the day i posted this. for some reason i had 4895 on the brain

 

[Fred_C_Dobbs]

Re: all my reloads are slow

There's other ways to test MV. Shoot at at least one range other than your zero range, preferably two. The further apart those are, the better. Use the same PoA for all targets, then record the vertical difference in PoA and PoI for all targets (at the zeroing range, this should be -- surprise! -- zero). Provided the manufacturer's listed BC for that bullet is reasonably accurate, we can calculate MV from those numbers.

Or I should say <span style="text-decoration: underline">I</span> can't but I have a terribly clever application that can.

 

[josephberry]

Re: all my reloads are slow

My buddy has a CED M2 that read incorrectly because the sensor distance was incorrect. He had to shorten the distance between the two. I think it has to be exactly 24 inches. This was after many conversations with the manufacture.

 

[Deisel]

Re: all my reloads are slow

The sensor distance does have to be exactly 24". You have to be sure to get both sensors completely on the bar. I found that spot on my bar and then used a black marker to draw a line so I was always able to put the sensors back at the same place.