So started reloading today, running Hornaday 140sst bullets, federal brass, federal primers, Winchester 6.5 staball powder. Now I had some factory Hornaday 129 super performance loads. COL was 2.655 from factory. My handloading has turned up with 2.654 OAL. But it hits the grove on the bullet perfectly. Now for my book spec is 2.690 OAL. Have I messed up?
New to loading 6.5creedmoor pls help
- Thread starter ih8ipods
- Start date
It is not a book "spec". It is just a note of what they used.
Your OAL will depend on your magazine length and the chamber throat of YOUR rifle..
When you chamber a round, does it pick up rifling marks on the bullet ogive?
If not, your OAL is shorter than max, and will work.
I deliberately load the first round long, then chamber it to get a feel of where the rifling is. Then seat deeper and deeper until a bullet does not get marks.
Your OAL will depend on your magazine length and the chamber throat of YOUR rifle..
When you chamber a round, does it pick up rifling marks on the bullet ogive?
If not, your OAL is shorter than max, and will work.
I deliberately load the first round long, then chamber it to get a feel of where the rifling is. Then seat deeper and deeper until a bullet does not get marks.
They will will be absolutely Fine but you should get a Hornady Lock N Load COAL gauge ! Then you can see where your are compared to the lands - RJ
]I just took a prepped 6.5 CM case and partially seated an 129 SST , then put that in the chamber and slowly closed the bolt.
So then I have an OAL cartridge for that particular bullit.
Wouldn’t that be the same idea as an lock and load gage?
Here’s a couple of groups from my rem 783 , 6.5 CM loaded at 2.710
So then I have an OAL cartridge for that particular bullit.
Wouldn’t that be the same idea as an lock and load gage?
Here’s a couple of groups from my rem 783 , 6.5 CM loaded at 2.710
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If the round is too long and the bullet engages the rifling, that will raise pressures compared to being 20 thou off the lands.
Unless you get really carried away, seating deeper does nothing to pressure.
Using a bullet in a prepped case probably won't give you an accurate measurement. Too much resistance in pushing the bullet into the case.
You can make a tool, similar to what you were doing. Take a Dremel tool with a cutting wheel and cut a slit in the case neck right down to the shoulder. This case will now hold a bullet loose enough that it will push deeper when it hits the rifling. Repeat several times until you get several reading of about the same OAL.
There is an easy way to measure a group. You appear to be measuring outside to outside and subtracting the bullet diameter.
The "no math" method is to just measure from the top of one hole to the top of the other (or bottom to bottom).
The cut in the case works like a charm. ThanksUsing a bullet in a prepped case probably won't give you an accurate measurement. Too much resistance in pushing the bullet into the case.
You can make a tool, similar to what you were doing. Take a Dremel tool with a cutting wheel and cut a slit in the case neck right down to the shoulder. This case will now hold a bullet loose enough that it will push deeper when it hits the rifling. Repeat several times until you get several reading of about the same OAL.
There is an easy way to measure a group. You appear to be measuring outside to outside and subtracting the bullet diameter.
The "no math" method is to just measure from the top of one hole to the top of the other (or bottom to bottom).
