Thread: Sticky bolt?

OK I think I may have cracked it. I have bought new brass, new powder and new pills. Measuring for OAL to the lands with the new bullet I figured I'd re-check my original measurement with the 150NBT. It appears I have 0.020" too less in my initial measurement so what was to be a 10 thou jump is now a 10 thou jam. I plan to run with CFE223 and 155A-Max bullets in my next brew. I can't see it being any better really but it's cost effective and available.
I hope this is the end of my issues. Cheers to everyone for your assistance.
James

Originally Posted by kiwijames

OK I think I may have cracked it. I have bought new brass, new powder and new pills. Measuring for OAL to the lands with the new bullet I figured I'd re-check my original measurement with the 150NBT. It appears I have 0.020" too less in my initial measurement so what was to be a 10 thou jump is now a 10 thou jam. I plan to run with CFE223 and 155A-Max bullets in my next brew. I can't see it being any better really but it's cost effective and available.
I hope this is the end of my issues. Cheers to everyone for your assistance.
James

If you are using Nosler Ballistic Tips be aware their ogive length varies WILDLY between batches......I have seen just over 45 thou...yep over 1 mm...FFS...

That may explain the variability I’m seeing in my 06 with 180 gn NBTs on 57 gn of 2209. I’m jumping them 40 thousand but have had 2 in 30 blow the primers out!

Greetings All,
Not just Nosler. I have found significant differences between three different Hornady projectiles. The differences were between older and more recent batches and not within the batches. In short later projectiles needed to be seated deeper due to a sharper ogive with the .22 cal 55 grains and distance from the lands was reduced in the 140 grain 6.5 interlock and 174 grain .303 round nose. The differences showed up on the chronograph but only on the target with the .303. As the projectiles are not all made in the same dies even in the same box some variation should be expected although I have not detected any. My minimum distance from the lands is 1 mm to allow for some variation. With the .22 cal 55 grains this wasn't enough.
Regards Grandpamac.

Using a comparator length instead of a COL (cartridge overall length) solves varying projectile length issues for hunting type reloading

School up on what a just touch or 5 thou / 10 thou jamb looks like on your projectiles ogive/shank

Then load accordingly for either mag fit or max accuracy


Here you can see rem mag ammo (162 ELD-X) that’s loaded for a ZCL (zeroed comparator length) of 2.641 inches

My just touch length in the Sako 75 is 2.645

So I’m jumping these projectiles to the rifling lands by 4 thou

Measure EVERY bullet that you make.

I always sort of thought that the ring on oglive caused by seating die will be pretty darn close to same on any and all projectile shapes...eg projectiles in same batch may have different overal lengths but the oglive will be the same so the distance to rifling by the fat curvy bit will be the same no matter what overall length is.

Originally Posted by 7mmsaum

Using a comparator length instead of a COL (cartridge overall length) solves varying projectile length issues for hunting type reloading

School up on what a just touch or 5 thou / 10 thou jamb looks like on your projectiles ogive/shank

Then load accordingly for either mag fit or max accuracy


Here you can see rem mag ammo (162 ELD-X) that’s loaded for a ZCL (zeroed comparator length) of 2.641 inches

My just touch length in the Sako 75 is 2.645

So I’m jumping these projectiles to the rifling lands by 4 thou

Measure EVERY bullet that you make.

Attachment 133368

Yes. I'm measuring my ogive. I'll do the first handful then check every 5th or so after. I've not struck much problems and I don't load closer than 0.010" typically not have I needed to.

Special Jimmy you big gut shooter. Whack those bullets in a bit deeper and off we go for a hunt.

Originally Posted by Ginga

Special Jimmy you big gut shooter. Whack those bullets in a bit deeper and off we go for a hunt.

Special Jimmy was great in Tropic Thunder

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Same sort of comedic movie like fuck ups occur when he’s on the end of his latest GPMG.

Originally Posted by Ginga

Same sort of comedic movie like fuck ups occur when he’s on the end of his latest GPMG.

Bwaaa Haa Haaa

I can only imagine.

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Originally Posted by Ginga

Same sort of comedic movie like fuck ups occur when he’s on the end of his latest GPMG.

Oi, fawn slayer. You can shut the fuck up.

OK, this shooter is now in the sorted pile.
It shows pressure very early. I'm now running 3-4 grains under Hogdons minimum load for CFE223 and the 155 A-Max looks good.

Velocity? Speed. You must have speed.

Originally Posted by Tahr

Velocity? Speed. You must have speed.

Its going fast enough I'll bet. I do need to chrony it but I'm really only keen on accuracy at present.
Put it this way, 49g was giving 2871FPS but was a very tight bolt. 47g only just had the faintest of feel in the bolt. I'm going to play with the 45-46 load a little and see what works.
I don't have a chronograph and have typically validated at range to get speed.