SAAMI COL specs for a 308 is 2.810. When I use the Hornady OAL gauge I get a COL of 2.900 for my rifle. A lot of the reloading books I have recommend a COL of 2.800. That seems like a lot of jump. Is it safe to load ammo that exceeds SAAMI specs? Is it normal to have a COL that much larger than SAAMI specs. I’m shooting a bergara.
The biggest reason for the shorter listed col in this case is because a 308 is a short action cartridge. The problem is not that you’re necessarily in danger of having the bullet contact the lands, but that if you seat the bullet out longer, it may not feed in magazines and feed ramps of the action.
So yes, you could load longer to experiment with jump, but it may mean you’d have to single feed.
But not specific to 308, the answer to your question is yes. It’s generally safe to load longer than the listed SAAMI col as long as you’re sure of your measurement and the ogive of the bullet doesn’t contact the lands when the bolt closes.
If the ogive contacts the lands, pressure can increase which can cause a dangerous situation. But loading past saami length is extremely common and safe as long as you measure carefully.
You should never have to push hard on the bolt to get it to close. If that happens, stop and check the seating depth.
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Some bullets do better loaded shorter than SAAMI specs. Barnes for instance, they like jump.
Every time I’ve purchased from a custom ammo maker like Choice or Copper Creek, they load their Barnes over 0.125 off of the lands and shorter than specs for COAL. And they more often than not, provide great accuracy
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I was completely missing the feeding aspect. 
Great information. Thanks
Interesting. When you look at the Hornady OAL gauge instructions it says you can start to see accuracy issues at .040” of jump.
I loaded my first rounds at 2.800 col and they shot great. 3 different powders and charges and all shot .6” to .8” groupings. I might find a more accurate load with seating depths, but not sure I can shoot much better than that.
I’ll play with the seating depth to see how long of a COL my gun can still feed well.
Yeah, one of the Great unknowns.
It very well may be different based upon bullet design. Hornady says that for their newer bullets, seating depth really doesn’t matter. So just seat it either 0.020 off for safety, or mag length, whichever is shorter. Hammer bullets says basically the same for their offerings. Barnes and Berger both say you should do seating depth changes. However, they say when you make a change it should be rather large. 0.025 or so. Not 0.002 like you read about in plenty of places.
Don’t know what nosler, speer, Sierra have to say about it.