Working a load, and no change in FPS?

[upsdownsideways]

Rifle: 6.5 CM, Krieger 26" barrel

Weather: 58 degrees, sunny, very light non consistent breeze

Range: 100 yards

I'll start with the google sheet from the FPS data I gathered;

Something I noticed off the bat... there was very little variation between the loads. In contrast to my hornady brass, I noticed a lot of differences.

Other than that, the groups were as follows. (They were all 3 rounders)

The last set shows no signs of over pressure on the primers.

I am not sure what to say?

 

[NamibHunter]

Strange to see 1.5 grains with almost the same speed. Flat spots (‘nodes’) are usually 0.6-0.7 for this caliber.

Did you start with a clean barrel? In what order did you shoot the groups?

Some barrels are very slow after cleaning until they get some copper fouling. Can take 5-15 shots.

Hot barrel can also speed up some shots with less powder if you let it sit and cook in the chamber for a while.

 

[upsdownsideways]

1) Clean barrel

2) Started at 40.0, worked up by .3 to 41.5.

The max-ish load I had with the Hogdon brass was 42.5, so I assumed my max load would be about 1 less as Lapua is more compressed.

 

[2aBaC̶a̶]

My 300PRC does this with RL26 and 208ELDs
76gr was 3005fps and 78gr was 3016. In between some were higher and some were lower but not in any logical order.

Ran it twice same results. Left me scratching my head.

 

[upsdownsideways]

My 300PRC does this with RL26 and 208ELDs
76gr was 3005fps and 78gr was 3016. In between some were higher and some were lower but not in any logical order.

Ran it twice same results. Left me scratching my head.

But mine never did it, until I changed from Hornady to Lapua brass.

Everything else stayed the same. lol Did you keep it at 76g to save 2g a round?

 

[2aBaC̶a̶]

But mine never did it, until I changed from Hornady to Lapua brass.

Everything else stayed the same. lol Did you keep it at 76g to save 2g a round?

I know right...

I'm going to run it a 3rd time starting lower and ending higher just to redeem my sanity.

What bullet and powder are you using?

 

[upsdownsideways]

Berger 140 Hybrid, H4350

 

[P_Mo80]

And your pretty confident you didn't have any issues with your powder measure / scale ... and chrono was as it should be? I know that sounds too obvious, but I've done that before!

 

[upsdownsideways]

Powder, no.

I even double checked the scale when I went home.

Chrono was working as far as I know ok? Not sure how to check otherwise.

 

[NamibHunter]

Powder, no.

I even double checked the scale when I went home.

Chrono was working as far as I know ok? Not sure how to check otherwise.

Strange indeed. Maybe you just got lucky and have a very wide node. My Lapua loads typically give good me nodes (flat spots in speed with low SD) that are 0.6 gn wide.

Some rifles have very flat speed curves close to (and beyond) max pressure. If you have a tight or min spec chamber, then thicker brass can get you to max a good 1 to 1.5 grain lower. However, your speed is probably too low for that to be the case. And Hornady brass would / should do the same.

Crony check: Recheck your old Hornady ammo, and if you get the same or very similar straight line as before, then you can trust your crony. Or try factory ammo you have measured before.

What crony are you using?

 

[upsdownsideways]

Strange indeed. Maybe you just got lucky and have a very wide node. My Lapua loads typically gives me nodes (flat spots in speed with low SD) that are 0.6 gn wide.

Some rifles have very flat speed curves close to (and beyond) max pressure. If you have a tight or min spec chamber, then thicker brass can get you to max a good 1 to 1.5 grain lower. However, your speed is probably too low for that to be the case.

Crony check: Recheck your old Hornady ammo, and if you get the same or very similar straight line as before, then you can trust your crony. Or try factory ammo you have measured before.

What crony are you using?

https://www.brownells.com/shooting-...graphs/beta-chrony-chronograph-prod25863.aspx

I borrowed it from a friend. I used it just a few weeks ago with the Hornady brass. It isn't the best, but it has worked well in the past.

I didn't keep any of the hornady ammo, once I shot the load up and decided to switch to Lapua, I gave the brass to a friend.

I will try the Hornady factory ammo, see where I get with it.

 

[NamibHunter]

https://www.brownells.com/shooting-...graphs/beta-chrony-chronograph-prod25863.aspx

I borrowed it from a friend. I used it just a few weeks ago with the Hornady brass. It isn't the best, but it has worked well in the past.

I didn't keep any of the hornady ammo, once I shot the load up and decided to switch to Lapua, I gave the brass to a friend.

I will try the Hornady factory ammo, see where I get with it.

My load development took a major step forward when i got an accurate crony. MagnetoSpeed is very accurate and about $160 or so. It is a good investment.

 

[upsdownsideways]

My load development took a major step forward when i got an accurate crony. MagnetoSpeed is very accurate and about $160 or so. It is a good investment.

Funny, I just ordered this one;

Competition Electronics ProChrono DLX Bluetooth Chronograph

The next generation of the ProChrono model based on a time proven design that has been measuring “almost anything that shoots” since 1985!...

www.midwayusa.com

It has good reviews both on the website and YouTube.

Never heard of the one you have. Should I cancel the order and get yours? I am not looking to go crazy on this lol

 

[ShtrRdy]

Funny, I just ordered this one;

Competition Electronics ProChrono DLX Bluetooth Chronograph

The next generation of the ProChrono model based on a time proven design that has been measuring “almost anything that shoots” since 1985!...

www.midwayusa.com

It has good reviews both on the website and YouTube.

Never heard of the one you have. Should I cancel the order and get yours? I am not looking to go crazy on this lol

Optical chronograph have always given me problems to some degree. After I got a Magnetospeed I can finally trust the measurements I am getting.

I still have to use an optical chrono for my pistol loads. Depending on lighting conditions and sun angle, sometimes it works.

 

[P_Mo80]

Funny, I just ordered this one;

Competition Electronics ProChrono DLX Bluetooth Chronograph

The next generation of the ProChrono model based on a time proven design that has been measuring “almost anything that shoots” since 1985!...

www.midwayusa.com

It has good reviews both on the website and YouTube.

Never heard of the one you have. Should I cancel the order and get yours? I am not looking to go crazy on this lol

Magneto Speeds are good. They attach to your barrel so your getting a true muzzle velocity and they are accurate! They will shift your point of impact on target a bit. I still use an optical for all handgun toying around.

 

[upsdownsideways]

Your Hornady data looks more normal...what’s the difference between the lapua and the hornady sheets? Small vs large primer? New vs once fired brass?

any differences you can think of in loading process, components, shooting conditions?

Only thing different is the brass. Same bullet, primer, seating depth. Both Hornaday and Lapua were brand new brass.

Maybe 5 to 10 degrees different between the two days? But nothing major.

Nothing that screams no major difference effecting powder charge weights.

 

[2aBaC̶a̶]

If you're only doing rifles i would suggest the Magnetospeed sporter. And get the little dongle to download to your phone.

 

[upsdownsideways]

Well, midway has a 15 minute cancelation close out

So, I will return it for a refund, but in the mean time I ordered the magneto.

 

[upsdownsideways]

Hodgdon lists 40gns as their max load and they call it “compressed”. Likewise, my Hornady book calls 40.9 gns the max, compressed. It just so happens that I shoot 140 Berger’s with 40 gns of h4350 in lapua brass (small rifle) at right around 2700 FPS and I don’t experience compression at my seating depth (~2.86 COAL). I can shake a loaded round and hear powder rattling around and don’t hear the powder crunching as the bullet seats. But, I get a noticeable reduction in shot to shot variation in once fired brass over brand new.

so, you might try this again with fireformed brass and your new chrony. I don’t think a flat speed curve is too unusual at close to max pressure. Your speeds do not seem unreasonable....if maybe a tad on the slow side...which could be your barrel.

you might try five rounds each starting a little lower...maybe 39, 39.5, 40, 40.5...and watch your speeds come up...if they stop coming up at around 40 to 40.5 gns or around 2600 FPS, that might be all you get from that powder/bullet/barrel.
Your numbers/target at 40.6 don’t look too bad but there’s not great results on either side. So maybe 40.4 to 40.8 is a smallish node. With the error in the data at 40.6 though, it’s a pretty small sample.

Would the brass choice make that much of a difference with my barrel tho? My hornady was 41.5 in the 2700s.

 

[upsdownsideways]

Ok, I'll wait for the magneto and work up a few loads in preparation.

Unless the chronograph took a dump, then this is a head scratcher.

 

[upsdownsideways]

If its not the chrony, then the only change is the brass from Hornady to Lapua.

 

[NamibHunter]

Only thing different is the brass. Same bullet, primer, seating depth. Both Hornaday and Lapua were brand new brass.

Maybe 5 to 10 degrees different between the two days? But nothing major.

Nothing that screams no major difference effecting powder charge weights.

So Large Rifle Primer Lapua brass, i. e. the new LRP option they started selling some 3 months ago? Should work very well. Lapua brass is a little thicker than Hornady - but not by much.

 

[NamibHunter]

Funny, I just ordered this one;

Competition Electronics ProChrono DLX Bluetooth Chronograph

The next generation of the ProChrono model based on a time proven design that has been measuring “almost anything that shoots” since 1985!...

www.midwayusa.com

It has good reviews both on the website and YouTube.

Never heard of the one you have. Should I cancel the order and get yours? I am not looking to go crazy on this lol

The famous Bryan Litz of Berger Hybrid fame did an accuracy comparison in his latest book. The optical screens need to be quite far apart before this style of crony can deliver true accuracy. And it is just a matter of time before a bullet strikes the crony.

i would go for the basic MagnetoSpeed ($160) if you are just starting out. Later on consider an upgrade to a Labradar ($500). Labradar does not change point of impact. Gucci solution, very accurate and convenient, but over priced IMHO.

 

[upsdownsideways]

So Large Rifle Primer Lapua brass, i. e. the new LRP option they started selling some 3 months ago? Should work very well. Lapua brass is a little thicker than Hornady - but not by much.

I guess? Lol. I only started 6.5 reloading in the past few months.

But it still doesn't explain the vast difference.

 

[upsdownsideways]

The famous Bryan Litz of Berger Hybrid fame did an accuracy comparison in his latest book. The optical screens need to ve very far apart before this style of crony can deliver true accuracy.

i would go for the basic MagnetoSpeed ($160) if you are starting out. Later on consider an upgrade to a Labradar ($500). Labradar does not change point of impact. Gucci solution.

I ordered the magneto, going to return the other when I get it.

 

[atepointer]

Funny, I just ordered this one;

Competition Electronics ProChrono DLX Bluetooth Chronograph

The next generation of the ProChrono model based on a time proven design that has been measuring “almost anything that shoots” since 1985!...

www.midwayusa.com

It has good reviews both on the website and YouTube.

Never heard of the one you have. Should I cancel the order and get yours? I am not looking to go crazy on this lol

i had this exact experience Saturday on that chrono(i think so it looks the same forget name it's buddy's). I actually went backwards on velo on a few loads. StaBall 6.5 and was bizarre watching my buddy's face as he wrote down the chrono data. Made zero sense to me as all 7 loads grouped from .5-.75", but was getting 50+fps variation from shot to shot. Will be trying a Magnetospeed along side it Wednesday to see if that is/was the case. I've triple checked my equipment at home....please let me know what you find!

 

[upsdownsideways]

i had this exact experience Saturday on that chrono(i think so it looks the same forget name it's buddy's). I actually went backwards on velo on a few loads. StaBall 6.5 and was bizarre watching my buddy's face as he wrote down the chrono data. Made zero sense to me as all 7 loads grouped from .5-.75", but was getting 50+fps variation from shot to shot. Will be trying a Magnetospeed along side it Wednesday to see if that is/was the case. I've triple checked my equipment at home....please let me know what you find!

I won't get it till this weekend, but I hope to find out next week.

Keep is updated for what happens Wednesday!

 

[atepointer]

I won't get it till this weekend, but I hope to find out next week.

Keep is updated for what happens Wednesday!

On my way this morning will have a Magnetospeed and the aforementioned both running.

 

[upsdownsideways]

How'd you make out?

 

[atepointer]

Magnetospeed 43.6g average was 2700 with other chrono last weekend was 2671
Magnetospeed 43.8g average was 2722 with other chrono last weekend was 2689

Hornady 6.5 140 HPBT and accuracy is best I've ever put on paper yesterday. Funny at 44g velocity drops down to 2705, but SD tightens up...accuracy goes down though. I'm learning a lot....at least I think I am? My tutor is a wealth of knowledge and being patient with me....I'm definitely smacking my head a lot as is the tutor.

 

[upsdownsideways]

That's pretty high powder charges. What brass?

 

[atepointer]

Sellier & Bellot from their 140g factory loads. I already worked up from the bottom no pressure signs even at 44. 43.6 and 43.8 were the sweet spots

 

[upsdownsideways]

It was delivered today, but this is my om weekend for work. Hopefully I'll get to it Tuesday.

 

[NamibHunter]

Sellier & Bellot from their 140g factory loads. I already worked up from the bottom no pressure signs even at 44. 43.6 and 43.8 were the sweet spots

Agree with prior post: That is a lot of powder to get below average speed for a 140 gn projectile. Most rifles will show pressure signs well before this high a powder charge.

Multiple possible explanations: Either the chamber is very roomy (very unlikely if Krieger chambered it), or the brass is exceptionally thin, or you have a slow batch of powder. Could also be a little bit of ‘All of the above’.

Can you clean and trim 5 pieces of brass to min (trim) length and report the weight? I posted a thread some years ago that related case weight to speed. That might be helpful to you.

You will find that once you have a good crony you can trust, a lot of problems just go away, and life gets a lot simpler.

 

[upsdownsideways]

So, got the magneto... does this look OK? The device looks like its a bit tilted up, but according to the road I used its still clear of the round.

 

[DaChank]

Looks like you actually need it a bit closer. You can also run it like that and increase the sensitivity if you need to. I always like to remove the bolt and look down the barrel to make sure I have clearance.

 

[upsdownsideways]

Looks like you actually need it a bit closer. You can also run it like that and increase the sensitivity if you need to. I always like to remove the bolt and look down the barrel to make sure I have clearance.

A bit closer in what way?

 

[DaChank]

I believe you want a quarter of an inch between the bullet and the sensor deck. You also want is as straight as possible

 

[upsdownsideways]

I think the barrel is tapered, as it is a bit tough to get it as straight as it is.

 

[2aBaC̶a̶]

Should work. Shoot it and find out. May have to increase sensitivity or use the smaller rubber spacer.

If you do a lot of load dev, invest in the phone jack adapter and download all the data.

 

[DaChank]

The phone adapter is a lot more useful for logging data than I thought but definitely more of a convenience thing

 

[upsdownsideways]

Should work. Shoot it and find out. May have to increase sensitivity or use the smaller rubber spacer.

If you do a lot of load dev, invest in the phone jack adapter and download all the data.

The smaller spacer was worse on the angle, I switched to the larger and it helped reduce the tilt.

 

[upsdownsideways]

How long is your barrel?

Edit: Nevermind I found it.

That seems slow for a 140, no?

It does for using the Lapua brass vs the Hornady.

 

[NamibHunter]

You can probably use some electrical insulation tape below the rubber spacer to correct the taper problem.

 

[upsdownsideways]

Well, I was all excited to give an update, but alas when I got to the range I had a 'WTF' moment when I realized I left behind a piece of the magneto. (Must have fell out when I was putting it in the box)

Sigh. I'll be going tomorrow before the rain starts. Damnit.

 

[upsdownsideways]

Ok, so with the magneto setup I tried the factory ammo first.

Hornady, 147 Match. Box says 2695 MV.

I did 2 test rounds.

2644
2661

Then I did my handloads.

41.5g

2691
2686
2687

41.8g

2695
2699
2671

Then I finished up with 2 more factory.

2666
2635

40 degrees today.

This is more inline with my Hornady brass, as the picture up shows.

Should I increase the powder a bit more? I am still not seeing any pressure signs. Ill post pictures later.

 

[NamibHunter]

Ok, so with the magneto setup I tried the factory ammo first.

Hornady, 147 Match. Box says 2695 MV.

I did 2 test rounds.

2644
2661

Then I did my handloads.

41.5g

2691
2686
2687

41.8g

2695
2699
2671

Then I finished up with 2 more factory.

2666
2635

40 degrees today.

This is more inline with my Hornady brass, as the picture up shows.

Should I increase the powder a bit more? I am still not seeing any pressure signs. Ill post pictures later.

Your rifle/barrel is just a little slower than average, nothing to worry about. It could be barrel characteristics, or chamber dimensions.

If i was confident there are no pressure signs in a case like this, i normally go up in 0.2 gn increments - and watch very carefully.

 

[upsdownsideways]

Your rifle/barrel is just a little slower than average, nothing to worry about. It could be barrel characteristics, or chamber dimensions.

If i was confident there are no pressure signs in a case like this, i normally go up in 0.2 gn increments - and watch very carefully.

I went up to 42.5, and I started getting hard bolt lifts (sticky bolt?).

At 42, I was pushing 2725 my ES at 6 and SD at 3,

I was happy with the combo. Just need to work on my seating depth.