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Aside from being off the lands or jammed into the lands, is there a given COAL or bullet seating depth that works well in the K-Hornet for 40 and 45 grain bullets, much like a standard load? I don't like how Hodgdon's load data for lil' gun shows 40grain Nosler BT seated to create a COAL of 1.9" and then some 45 grain SP are seated shorter to 1.75".

If I fill one of my fired K-hornet cases with lil' gun, 13.5 grains fills it to the start of the neck. If I drop a 40 or 45 grain bullet on top of this charge the COAL measures about 1.85 or less with the bullet sitting right on top of the powder. Is lil' gun a powder that likes to have more compression, because the 40 grain v-max that I loaded to 1.905 had a horrible velocity spread and definitely could have been seated deeper as I only had 12.0 grains of lil' gun to start. They are only seated about half way down the neck and have less bearing surface because of the boat tail say than a 45 grain flat base.

In the future, I am going to try rem 6 1/2 primers instead of CCI 400 and I will try the Lee Factory Crimp. Hopefully these will help with initial pressure and bullet tension.

Would it necessarily hurt to seat the remaining rounds I have loaded of 40 grain V-max, 12.0 grain lil gun' (starting load) and CCI 400 slightly deeper to around 1.85 and measure them through the chronograph.

Thanks,

Eric
 

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Welcome to the forum. Rules are to join in and have fun and play nicely with the rest of us kids.

The maximum I have for the K-Hornet is 1.723", same as the Hornet, but you can go longer if your throat allows it and if you are not feeding from a magazine that would be jammed by the greater length? In general, people choose whatever seating depth is most accurate for them. You take a light load and try different depths until you find the best one. Then you work the powder charge up to optimum. Dan Newberry's round robin method works well for identify accuracy sweet spots in an organized fashion. You can use either powder charge steps or seating depth steps.

If you just want a general purpose rule of thumb for general purpose ammunition, then seat the bullets so the bottom of the bearing surface (the full diameter portion of the bullet) is one caliber (.224") deep into the case mouth. There are two exceptions: If that is deeper than the bearing surface is long, you stop when the bearing surface is just all the way in or maybe 20 thousandths outside the case. If the resulting cartridge exceeds the maximum COL or results in a bullet touch the throat of the rifling, in which case you seat as deeply as necessary to prevent either one.

To find what COL will do fit the first criteria, note the maximum case length and measure the average length of the your bullets. For a boattail bullet, also measure the length of the boat tail. Then use:

COL = case length + bullet length - seating depth - boat tail length

For a flat base .22 Hornet bullet, this just becomes:

COL = 1.378" + bullet length -0.224" = 1.154" + bullet length.

If the above COL is over 1.723", use 1.723". If the above puts part of the bullet ogive below level with the case mouth, adjust it outward until it no longer does.
 

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Rather than using rifle primers try using small pistol primers. Search for Rocky Raab's pet load for the hornet on this site. He uses I believe WW cases, small pistol primers, LilGun Powder @13.0grains and Lee crimp die for consistant results.
 
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