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View Full Version : rubber o ring on a k hornet case?



samwithacolt
02-28-2015, 06:35 PM
I'm sorting through my k hornet brass for the upcoming gopher season. A lot of my cases show signs of head seperation and I'm going to fireform some new ones.
I have heard of guys using an o ring on a .303 British case to keep them back against the bolt face while firing, then neck size only. I load 35 gr vmax right up to the lands anyway, but those little cases are very weak. I did'nt aneal them after firing before, will on the next batch. Anyone tried an o ring on hornet, or are the too small?

ratboy
03-02-2015, 02:47 PM
i would think that if you had enough room for an o-ring on the case then the headspace would have to be excessive.
i think your plan of annealing them and neck sizing should be plenty for better case life.

skeettx
03-02-2015, 03:08 PM
You are already doing this
Seat the bullet out so closing the action is a tight fit.


Next possibility
Put a SMALL bit of tape on the shoulder of your normally loaded Hornet case and when the gun fires, the case will be formed.
Remove the SMALL bit of tape and on the next shooting that dimple will expand.

Next possibility, use a lighter load to form the case and then load as normal.

Mike

p.s. you did not mention what action you are using.

flounderman
03-02-2015, 03:22 PM
The hornet headspaces on the rim. Apparently you have a headspace problem and I wouldn't be full length resizing. No reason to full length a case to be fireformed to an improved chamber. When you size the neck, don't size it all the way to the shoulder.

fryboy
03-02-2015, 04:38 PM
since the khornet actually headspaces on the shoulder i do a few pronged approach ...one thing i do to new or once fired brass is to neck up to a 6mm and then back down with the shoulder neck junction in the correct space , then when i fire form i use a very very lite coat of oil on the neck ( it helps keep it from grabbing/sticking so that it blows out the brass from there rather than the shoulder , i've had new factory ammo split upon first firing that i didnt oil ) of note i do not recommend this on any other cartridges , i also anneal after creating this shoulder and jam the first fireforming projectile into the lands
as for the rubber o-ring .... amigos he isnt thinking a huge thing - more like the lil bitty ones the dentist uses on braces etc , it goes under the rim and holds the case head against the bolt ... for me it isnt needed as the shoulder i create solves this for me ( YMMV ermm your mileage may vary )
i also neck size only when at all possible , if you do a partial or full length sizing i'd suggest holding it to a minimum to save on working the brass

samwithacolt
03-02-2015, 11:16 PM
The problem was that the primers were sitting out a little after forming from regular hornet brass. The brass was'nt stretched all the way back on the 1st firing, so they were overworked before they ever got formed.
I need something to keep the rim back against the bolt face on the 1st firing. I can try loading the bullet right into the lands, but the rims are so thin I'm wondering if the firing pin will seat the bullet deeper as it pushes the case forward.
The rifle is a Ruger(big mistake, wish I'd waited and used a CZ for the whole k hornet project).
There are very small o rings available online to order, and I know guys do it with .303 Brit.
If I can blow the shoulder out on the 1st firing and then aneal, I'm golden. Right now I have some cases that are starting to seperate on the 2nd firing(they were'nt anealed either). I only size about half of the neck. Partly for headspace and partly because my rifle likes the 35 gr vmax seated out to the lands.

ratboy
03-05-2015, 11:16 PM
The problem was that the primers were sitting out a little after forming from regular hornet brass. The brass was'nt stretched all the way back on the 1st firing, so they were overworked before they ever got formed.
I need something to keep the rim back against the bolt face on the 1st firing. I can try loading the bullet right into the lands, but the rims are so thin I'm wondering if the firing pin will seat the bullet deeper as it pushes the case forward.
The rifle is a Ruger(big mistake, wish I'd waited and used a CZ for the whole k hornet project).
There are very small o rings available online to order, and I know guys do it with .303 Brit.
If I can blow the shoulder out on the 1st firing and then aneal, I'm golden. Right now I have some cases that are starting to seperate on the 2nd firing(they were'nt anealed either). I only size about half of the neck. Partly for headspace and partly because my rifle likes the 35 gr vmax seated out to the lands.

if you can close the bolt, i dont see why it wouldnt work.
if the o-ring is too soft you could make a ring of copper wire but i would expect the o-ring to get the job done.
i wonder if annealing before forming would help or hurt?

leadman
03-06-2015, 12:40 AM
I just do what P.O. Ackley recommended, fireform with a full load. Have not had any issues in over 15 years of shooting the Contender in 22 K-Hornet or the 30-30AI.

Preacher Jim
03-06-2015, 08:04 AM
I use max hornet load to fire form and in 35 years I have not lost a case.
I anneal my case after formed my head space is set at minimum. Neck size only. If needed I will full length size but not bump shoulders back

samwithacolt
03-07-2015, 10:39 PM
Tried a couple of regular hornet cases today with a peice of rubber band tied around them. There was a little resistance on closing the bolt, but the primer stayed flat on the bolt face and the shoulder was blown out nice and sharp. I can aneal them now and partial neck size, so they should be fully supported from now on.I need a dollar store bag of rubber bands.

Nrut
03-14-2015, 05:54 PM
I would over expand the necks on new brass then set my sizing die to leave a false shoulder that gives you proper headspaced brass for fire forming as posted by fryboy​ ...

Sounds like who ever AI'd your Hornet didn't set the barrel back when he did the job..

Geezer in NH
03-14-2015, 09:35 PM
The o-ring on a 303 Brit is to keep the case centerere in the most likely oversized chamber to keep the case concentric when it expands not to hold it against the bolt

barrabruce
03-18-2015, 06:14 PM
Plus 1 with geezer

New brass I load to seat into the lands and shoot.
Factory ammo can get a lop sided if shot in mine.
Basically all I did was seat long then drop the charge a little to keep the case concentric.
A bit of tape before the web may help in that matter too.
I only size enough of the neck to hold a bullet.
clean up the mouth square and haven't worried about anything else.
primer pockets get too loose usually before for I have other issues.

The non concentric web/case junction gives out quicker than a nice concentric one thou.

I don't load mine max pressure and still using some I made 30 yrs ago.....then again it sat in hibernation for a long time too.

2-3 ths of a grain lower will can mean the cases will last 10-15 or 50 loadings.
I just load till its accurate and stop at that and have always been happy.
If not buy a 222