I am a novice reloader. Have 2 280AI's. One is being built and other is being stocked after a recent build. Owned one prior but did not personally load for it. I hit pressure signs (sticky bolt) on my new gun. Was trying it out in an old stock. 75 degree temps and close to the lands. This was with 150 TTSX and 160 Accubonds. Both loads were slightly below published max loads. I just bought a chronograph. Have not tried it as have no cf rifles at home right now. what will the chrono likely tell me about this rifle's performance? Will the below max loads likely be faster than the book or could I just have a chamber/barrel that does not like to be pushed? Hate to ask a dumb question but unsure how to use the chrono as a reloading tool. Know it will tell me speed for ballistic calculation. Is the chrono otherwise there to show unusually high velocity absent other pressure signs as a safety tool? Thanks.
Look at a LOT of data,as much as you can,to get an idea of what the cartridge is capable of in different barrels to get a weighted average of velocities. A pattern will emerge.
Confirm with your own loads and watch the chronograph. Also watch primer pockets and other "traditional" pressure signs. They may not be perfect but they are all you have unless you buy pressure equipment.
Expect anomalies. No two barrels are ever the same, even if from the same maker, chambers cut with the same reamer, same day.
In reading others experiences,toss out the exceptionally high velocities they obtain, and the exceptionally "low". The truth will likely be in the middle range of things.
Remember that within ear shot of this site are (how many?) a few hundred 280 AI users(?). That's a few hundred different barrels, with varying dimensions,cut with different reamers,different mixes of components,fired under different conditions and over that many different chronographs. If results are identical to yours it's more luck than design....but it'll still happen.
Just because someone else gets 3200 with a 140 gr bullet from a 280AI does not mean you will...too many variables.
Never owned one, but seeing 3300 fps from a 140 gr bullet from a 280AI would have me on red alert,whether it showed pressure signs or not.Even larger cases do not alway go that fast in some barrels.
Get some factory ammo in the same bullet weight and see what it does. Word is the 280AI is loaded pretty hot and if your barrel is getting substantially more velocity than the factory stuff from your hand loads, you may want to back off.
