BulletQuestion

[DEACONLLB]

I ran into a probblem the other day and wondering if any of you fellows have ever had this problem.
I have a number of 223 rifles and as we have to have a 60 grn or bigger to hunt deer in Oklahoma I picked up a box of 69 gr.match grade but are made in Serbia and in sighting in the rifle they were not leaving a round hole but a keyhole type hole. I tried one in the end of barrel and found that they went right in I then tried a number of other brands and found that they would not go in so it would seem that these are undersized so have any of you fellows ran into undersized bullets? This is the only time I have had this happen.

Deaconllb

[jason280]

Do you have acces to a set of micrometers?  If so, measure the bullets and go from there.  If they are fitting loosely in the muzzle, then they do sound undersized (and would likely not stabilize). 

[sweetwyominghome]

You are likely shooting these in a twist that won't stabilize such a long bullet. You need a 1:9 and preferably even a 1:8 for best results.

[Grumulkin]

You are likely shooting these in a twist that won't stabilize such a long bullet. You need a 1:9 and preferably even a 1:8 for best results.

BINGO!

The twist of T/C .224 caliber barrels is 1:12 and they don't stabilize long pointy bullets well.  There is hope however.  I shoot Speer 70 gr. Semi-Spitzers in my T/C barrels in 222, 223 and 22-250 and they stabilize just fine.  They kill all manner of varmints and deer well.  In fact, I took a deer a 360 yards with one of these bullets out of my 22-250.

[DEACONLLB]

After the comments here I did some more searches and Ladobe said the twist for TC 223 barrels are 1-12 as was mentioned also in above post and and I found a chart for Mosberg SSI 1 223 barrels and the twist rate is 1-9 so that explains the perfect hole from ssi1 and the oblong hole from the TCR
Thanks for help

Deaconllb