Help with OAL

[proraptor]

So I was looking for one of those nifty stoney point OAL guages and it looks like they are discontinued.....Does anyone else make one? Anyone in Orange County sell them?

Or does anyone know the perfect OAL for the Savage 10FP in .308?

[Cazach]

I believe Hornady picked up the Stoney Point gauges and are now selling them under their brand name.

Midway or Brownells should have them.

[StukaJr]

You could just "smoke" a dummy .308 cartridge and find out that way - unless you are not interested in doing it that way of course

[proraptor]

You could just "smoke" a dummy .308 cartridge and find out that way - unless you are not interested in doing it that way of course

Explain....Ive never heard about this...

[phish]

Stuka's referring to the method of seating a bullet out long, getting candle soot on the bullet, then seating it into your rifle to find out where the bullet touches the lands.

The case mouth has to be at the right size so the bullet stays put when it's extracted. The flip side is if the case mouth is too tight, you run the risk of jamming the bullet in there which you'll have to pound out with a dowel.

It's just easier to get either a Stoney Point tool or Sinclair's gauge.

Savage's factory chamber is pretty good with either the 168 or 175 Sierras. A 168 is actually about 0.020" away from the lands when seated to about 2.80". YMMV, don't know how consistent Savage's chamber specs are from lot to lot.

[PistolPete75]

oal depends on your what type of bullets your using. if you going 168grain sierra match king, oal should be about 2.8 (i would double check with a lyman's handbood). definitely get an oal guage. i bought mine from dillon for about $30.

[StukaJr]

Explain....Ive never heard about this...

Take a resized and tumbled casing (no primer, no powder) and cap it with the bullet you'll be using - set the bullet with your press just enough in so it can't be dislodged. Chamber it in your rifle - most likely the bolt won't close as the bullet is too far out. Continue setting it deeper and deeper in small increments until the bolt closes on the dummy cartridge. Now, hold the bullet over a lighter/candle flame until the bullet is sooted black (make sure you are not "smoking" a live cartridge, obviously) - chamber the smoked cartridge in your rifle. Remove the cartridge and observe the sooted bullet - you should see the clean areas where rifling of your barrel rubbed off the soot. Wipe the bullet clean, set it an increment deeper, re-soot and repeat. Your Maximum OAL is that last increment where you inserted and extracted a still sooted bullet.

Some care must be taken when chambering a sooted dummy cartridge - drop it carefully into the chamber and then close the bolt on it, so the soot does not rub off by banging it around until it hits the throat of the barrel.

I also assume that you'll be chamber loading these rounds? Custom OAL rounds often won't fit some of the bolt action rifle magazines... I personally never found Maximum OAL to be that big of an improvement - heavy crimp does a good enough of a job in getting the bullet into the grooves with good consistency. Max OAL becomes a nuisance actually, if you are shooting multiple rifles in the same caliber.

[30Cal]

You guys have complicated things a bit. Skip the candles and gages. Here's what I do and it gets me within 0.003" of what I get using a dedicated compairitor.

1. Load up a case. Seat the bullet out long by say 0.050".
2. Stuff it into the chamber with your thumb

If you have to use a thumbnail or screwdriver to get it back out, then the bullet is in the lands.

3. Seat the bullet deeper by 0.005" and repeat. When the cartridge drops clear from gravity alone, measure the OAL. This is where your lands are. Then shorten it up by whatever you think (0.020" deeper is a pretty good generic setting depth).

On short, lightweight bullets, you want to make sure you have approx. one caliber of bullet length inside the neck (ie you want about 0.30" of the bullet inside the neck to assure decent tension).

Ty

[Prc329]

You are going to have to check yours to be sure but I am loading at 2.83. that is what I measured using my hornady gauge and 175g SMKs. I loaded some 168 to 2.84 and the sot well but I think 2.83 is where I will stay. The bullet got stuck in the grooves at 2.835 so I backed it out to 2.83. I'm going to try the new loads on the 21st.

[ocabj]

I use the Stoney Point (now Hornady) tool. It's a good reference tool, but the key thing to understand is that the reading is subject to the headspace (shoulder) length of the case provided with the tool. Thus, the precision (as opposed to accuracy) of the tool is debatable.

The method outlined by 30cal and the other posters is probably a better way to do it. I use the Stoney Point tool simply because I found it simple to use.

Finding the COL with respects to the lands is an artistic method to a scientific end.

Personally, seating depth should be one of the last things you need to fine tune. Consistent case prep first. Find the proper powder and powder charge weight. Find a good grouping load. Then fine tune the seating depth to see you can get the group size to shrink. It's fine to want to know what the seating depth is for a specific bullet to the lands in your rifle. But don't get too obsessed with finding the correct seating depth by the one-thousanths of an inch.

[Prc329]

Very good point ocabj

[proraptor]

I think Ill follow your advice ocabj....Thanks a lot guys for all your help