PT Unit is Functional

[ET]

On my last range visit my shooting session was interrupted after 2-shots because of a range rule not being followed (Visitors Badge).
But did confirm that the PT unit is functioning.
While loading for my verification load, I found a real difference in loading resistance of about 7lbs. between the two loads. Okay let’s see what happens. AJ was correct with his comment about altering load resistance changes peak pressure.



Another thing I need to be mindful of is my Chrony distance from the muzzle. Because I’m trying to obtain readings as close as possible to muzzle velocity that distance needs to be as constant as possible. So I need an adjustable spacer bar to ensure my shooting rest is always at the same distance from the Chrony bracket. Another project to work on, chuckle.

Ed

[jims]

I would not have guessed it would be that significant.

[ET]

Sept 9, 2019 19:07:18 GMT -5 jims said:

I would not have guessed it would be that significant.

You're not the only one surprised to see this much difference. I will be including testing of load resistance by doing different bullet/sabot OD's. Having a load gauge I can now more closely monitor load resistance.

Ed

[AJ]

Congrats on getting your toy up and running. Yep, this is another reason to watch when shooting at the max level. If your pressure level is 50k psi and you are regularly shooting to that level, a tight bullet will definitely make it way past your limit. YMMV It might be interesting to see how linear the curve may or may not be as the pressure levels are increased. At the lower end you saw 8k psi increase. My increase was I believe 5k psi in the 45k psi range (45k to 50k psi).

[ET]

AJ, thanks for the congrats as it's been a struggle to get this far, chuckle.
Interesting thought about curve linearity vs pressure level if it exists.

Ed