Short chamber?

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08-03-2018, 03:30 PM
mbohuntr

Short chamber?

I finally was using my Hornady gauges to check the lands on my .223, and While I was fine with Nosler Varmageddons, I measured the chamber for hornady 55gr sp. bullets. My hornady book gave me a OAL of 2.20", And I used that as my max until today. The guage measures the lands at 2.815, and my lee bullet seater die bottoms at 2.815 on the ogive, giving me a OAL of 2.53" !!!

So I was jamming it by .33" !!!!!!!! What am I missing? Do I have a Short chamber? All other measurements fine.. Apparently it was a good thing I don't use a lot of neck tension....
08-05-2018, 09:30 AM
Robinhood

You are measuring something wrong. No 223 has lands anywhere near 2.815. Did you forget to subtract the length of the Hornady pieces from your final dimensions?

https://www.luckygunner.com/labs/wp-...r-791x1024.jpg
08-05-2018, 11:59 AM
mbohuntr

Quote:

Originally Posted by Robinhood

You are measuring something wrong. No 223 has lands anywhere near 2.815. Did you forget to subtract the length of the Hornady pieces from your final dimensions?

https://www.luckygunner.com/labs/wp-...r-791x1024.jpg

I guess I didn't do to well in the explanation... You're right, the Ogive measurement is 1.815 if I bottom out the seating die. I forgot to subtract the inch. My chamber is also 1.815. and the new OAL is 2.150" So... That means the book OAL was 2.20, and the Ogive was 1.865" so, about 50 thousandths jam in my rifle?
08-05-2018, 12:15 PM
Robinhood

How did you find the lands?
08-05-2018, 12:22 PM
mbohuntr

Quote:

Originally Posted by Robinhood

How did you find the lands?

I used the Hornady OAL guage, brass, and a 55gr. soft point. Made sure the brass was threaded tight, pulled the plastic piece back, pushed the rod in until the brass bottomed, then used the plastic piece to push the bullet in till it stopped, locked the plastic piece with the thumbscrew, removed, and measured.

Repeated several times.
08-05-2018, 12:43 PM
Robinhood

I used to do that until I realized the Hornady case was a different headspace than my chamber. But that is less than .010.

Nothing there to really improve on. At least a .050 shorter cartridge OAL is not as bad as .330. Your options are shoot the thing and lengthen with the throat erosion or you could get a uni-throater and claim about .065 - .080 more throat(or get a smith to do it). OR, Get another barrel and sell that one with full disclosure.

Honestly, I would let the lands tell me where to put the bullet and load them that way. As long as your not crunching powder you will be OK. I always liked H335 for this chore.
08-05-2018, 02:27 PM
mbohuntr

I loaded some up earlier for a ladder test, and they go hot near the top of the range. Nothing more than flattened primers, and stiff bolt. Now I'm going lower, and not jamming. Perhaps I'll find an accurate combo this time. Noslers work great, just not cheap.
Thanks a lot for the help!
08-05-2018, 11:09 PM
Texas10

I found that when switching from the 53 V-Max to 55 FBHP Hornaday, the OAL and CBTO was much shorter. I had worked on it for an hour because I didn't believe it could be so short, but it was. Much different bullet contour between the two. Try the 69 TMK to gain some case capacity, or the Lapua 69 gr Scenar L on sale now at Grafs for under 20 cents each. At that price they're cheaper than the Hornaday 68's and shoot much better.

You can always go with H335 too.
08-06-2018, 01:21 PM
mbohuntr

Quote:

Originally Posted by Texas10

I found that when switching from the 53 V-Max to 55 FBHP Hornaday, the OAL and CBTO was much shorter. I had worked on it for an hour because I didn't believe it could be so short, but it was. Much different bullet contour between the two. Try the 69 TMK to gain some case capacity, or the Lapua 69 gr Scenar L on sale now at Grafs for under 20 cents each. At that price they're cheaper than the Hornaday 68's and shoot much better.

You can always go with H335 too.

I will, thanks!
08-09-2018, 08:01 PM
bigedp51

I remember when I started loading after I got out of the service in 1973 and all I had was a plastic Lyman vernier caliper and kept things simple.

I bought Hornady bullets with a cannelure and seated the bullets to the middle of the cannelure. That way I didn't have to worry where the lands were or about OAL. :first:

But then again the average deer shot the woods of central Pennsyltucky is 40 yards. And the favourite rifle was a Remington 760 pump. (Amish machine gun) :biggrin-new:
09-16-2018, 04:47 PM
mbohuntr

I was looking around the other day, and came across this.. thought I'd share since that's exactly what I found. They are accurate, and inexpensive, just be aware of the seating depth....

Rated 4 out of 5 starsSuper Accuracy, Excellent Price

Submitted 3 years ago
By Sxgun
From Utah

Verified BuyerVerified Buyer

Verified ReviewerI bought these bullets in a 1000 round bulk package. I couldn't be happier with them for the price. These bullets have a relatively short nose section and a unique shape. Rather than having a gracefully curving ogive, this bullet has more of a cone shape and have a distinct line where the cone meets the cylindrical shank of the bullet. This shape results in the OAL needing to be significantly shorter than the "nominal" or maximum SAAMI spec. to avoid the bullet being jammed into the rifling lands during chambering. Seating 0.010" off of the lands in my rifle resulted in an OAL of 2.185". By comparison, and on the other end of the spectrum, the 53 gr. Hornady V-Max has an OAL of 2.310" to be 0.010" off the lands in the same rifle. OAL of 2.185" puts the cannelure right at the case mouth and looks right, cosmetically. The short ogive also results in the bullet having a relatively long shank giving this bullet lots of bearing surface length for bullet/barrel alignment. This may have something to do with their accuracy. At the range, sub 1/2 MOA accuracy was easily attained in my 1 in 12" twist .223-Rem bolt gun. The best group happened to coincide with the maximum charge weight listed for RL-15. I have not chrono-ed the load but the data suggests that it should be around 3350+ fps. Terminal performance: This is where you have to decide if this bullet will fit your needs. This bullet is not explosive or frangible. At the velocity listed above, I have heard several ricochets whine off into the distance when hitting hard dirt. My quarry has been mainly jackrabbits. I have had mixed results. I have made several hits resulting in massive destruction and others that are not that different from what you would expect from an FMJ, requiring follow up shots. It appears to me that hitting bone is required for positive expansion in jackrabbit sized game. From my experience, these have the terminal performance similar to a big-game bullet, mushrooming out but retaining a high percentage of their unfired weigh. However, I would not consider this to be a big-game bullet any more than I consider .223-Rem to be a big-game caliber. For the price I can't imagine a better bullet. This is the reason that I am a big fan of Hornady. I have always been pleased with their products and in my opinion, they are consistently the best for the money.