Recent content by Opa-lopa

Got an LL Bean backpack that has a single shoulder strap & a waist belt. You can switch shoulders in a matter of seconds, and there’s nothing in the way when you shoulder the rifle. It could be a bit bigger internal capacity, but I’ve learned to adapt.

It’s all about the diameter control of the throat. The 7mm PRC has a cylindrical throat of .2846, while the 7mmRem mag has essentially the same diameter but a 3 deg taper. That mean the Rem throat is 0.006” larger just in front of the case mouth, allowing the bullet to tip relative to the bore...

Gaussian distribution is for large sample sizes, T distribution for n<30. Instead of using Extreme Spread, get targeting software & use average of Horizontal & Vertical std deviation.

if you compare the “Students T” distribution (small sample size distribution) to the Gaussian distribution, when number of samples = 30, the Students T is within about 0.1% of Gaussian. What level of match/confidence is acceptable? 90%? 95? 99?

Velocity “flat spots” are a figment of small sample size; ignore them. Plot the data, compare w/ velocity vs charge weight from load manual. Is your data above or below the manual? If you’re below, you probably either have a shorter barrel or worn throat. If you’re above, it’s either due to a...

Ditch the Strelock, switch to Hornady 4DoF w/ zero angle.

Radar is accurate to within 0.1%, or 3FPS/3000fps, not 1%.

Truing is what you do when the app doesn’t provide accurate answers.

Hornady 4DoF is the way to go. All else is approximation.

Had a 742 four decades ago, with handloads best i could do was about 2” ES for 3 shot groups at 100 yards. Inconsistent forearm torque, shotgun trigger & loose working tolerances aren’t conducive to small groups. This is a gun intended to spray lots of lead quickly in the direction of whitetails...

LMT makes hi pressure bolts, FWIW.

Velocity “nodes” are the result of insufficient sample size & change test-test. Plot a straight line thru your data (in Excel) & see where you are relative to load manual. You want to have the same change in velocity w/ change in charge weight as the load manual, and you want to know if your...

Have personally taught perhaps a half dozen people.. 4 in a formal class where they paid to learn, one freebie, one extended pay by the hour mentoring on several rifle calibers.

Pressure isn’t a factor in barrel erosion? Respectfully disagree.

Until it doesn’t. Seen bullet structures slump, causing increased bearing length, higher resistance pressure & chamber pressure w/o increasing MV. It’s like hitting a wall.