Help me with oal

[Slab74]

So I just tried using my Hornady oal gauge and bullet comparator. Rifle is a GAP PPR in 6 creed. This is my first time doing this. My numbers came out to:
2.258
2.250
2.256
2.265
Bullet was 105 hybrid. I know that the last one was pushed a bit harder than the rest. Two questions, do these numbers seem to be in the ballpark? If numbers seem ok, suggestions on starting load? Rifle has 160 rounds down the tube. All prime 115.

 

[Rocketmandb]

So I just tried using my Hornady oal gauge and bullet comparator. Rifle is a GAP PPR in 6 creed. This is my first time doing this. My numbers came out to:
2.258
2.250
2.256
2.265
Bullet was 105 hybrid. I know that the last one was pushed a bit harder than the rest. Two questions, do these numbers seem to be in the ballpark? If numbers seem ok, suggestions on starting load? Rifle has 160 rounds down the tube. All prime 115.

Remember that every chamber is slightly different.

How much harder did you push the last one in? I'm guessing that one was slightly jammed into the lands. Now - the nice thing about this, and Erik Cortina goes into this in one of his videos, the exact measurement doesn't matter. Pick one and use it as a reference point going forward. You'll be testing different seating depths against this reference point. From what you've got, you had two very close at 2.256 and 58. Use one of those and move on to testing different seating depths against it.

 

[OHwelder]

My experience with the Hornady OAL guage is that it takes a real feel for when you are touching the lands and its very easy, as you can see, to push it in too far. I aet the bullet back in the case and make sure I have the case seated properly, then ease the bullet ahead until it stops. Like I said, its feel. I would try again and see if you don't end up around 2.50 - 2.54. As far as starting loads, I'm at 44.7 of RL26 behind Berger 109's. You can call Berger, tell them powder and bullet and they will get you started.

 

[Aftermath]

One of the things I started doing many years ago was to use a sharpie and "color" the entire bullet. As it touches the rifling, that color will be marked a little. You can judge by the depth or length of those marks just where you are in OAL.

 

[C.R. Adams]

something isn't quite right with your "touch". the numbers should be closer to each other than that

 

[clcustom1911]

When you are pushing the bullet to touch the lands, you should use very light pressure.

What I do is get a fired case, cut a slot down each side of the neck, clean burrs, neck size the case, take extractor off the bolt, insert slotted case with bullet into chamber, bullet should be just inside the case neck, Pushthe casing into the chamber with my pinky, insert and close bolt, remove bolt, take cleaning rod and insert felame end into muzzle end slowly (so it captures the point of bullet, gently push cartridge out of chamber, catch with hand.

Measure OAL with comparator. There's just enough neck tension to keep the bullet in place as you do this. Repeat the measurement 3-5 times Intel you are within 0.001-3" of each other.

 

[TheOfficeT-Rex]

There's quite a bit of finesse required to get consistent readings with the hornady tool. I find I have to stop as soon as I get any resistance, and even then I'll only get readings within about 2-3k of each other.

 

[Steel head]

There's quite a bit of finesse required to get consistent readings with the hornady tool. I find I have to stop as soon as I get any resistance, and even then I'll only get readings within about 2-3k of each other.

This.

 

[Slab74]

This was my first run and I appreciate the advice. I’m going to start from scratch again see if I can get a better feel. My .308 came in all within.003 of each other, 168 amax. I would guess that the small, longer bullets are harder to get the feel for.

 

[rustyinbend]

This was my first run and I appreciate the advice. I’m going to start from scratch again see if I can get a better feel. My .308 came in all within.003 of each other, 168 amax. I would guess that the small, longer bullets are harder to get the feel for.

Make sure the bullet moves VERY smoothly in the modified case. I had this same problem until I wrapped some fine-grain sandpaper around a punch, and took some of the surface off the inside of the modified case neck. Then I added just a super-light coat of oil around the bullet. Once you know the bullet is receiving "zero" resistant to being pushed, then start it well back, push very gently, and stop when you feel any resistance whatsoever. Do it 10 times. 2 or 3 of them will be throw-aways, and the rest should give you an average that makes good sense as a starting point. Back off slightly (15/1,000) ... and go shooting. It should work.

Side note ... my issues also were (a) magazine length, and (b) didn't have enough shoulder bump.

(a) caused me to have to back off further than those measurements, and (b) resulted in about 20% of my cartridges not chambering during my first tests.

Learned both lessons, and doing better now. Good luck. Keep learning. Keep asking.

 

[Slab74]

So I ran the test again and I ended up with 2.249 5 of the 8 tests I ran. The rest were within .003. Thanks for the advice. I did my brass prep today and tomorrow I’ll start rolling some up.