How compressed is too compressed?

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When running compressed loads (high volume, slow burning powders), is there a point where compressing the powder can cause burn rate variance or potentially move the bullet in the case neck? My Tikka 300 WSM throat wasn't as long as I'd hoped for, and I'm being a tightwad and trying to avoid dumping $250 into a throater to fix it. At 68 grains of RL23, the powder fills right to the bottom of the neck, and the bullet seats with the base of the bullet slightly below where the shoulder starts on the case body. I've already ordered a VLD seating stem to help eliminate the marks on the bullets from compressing the powder this much... It does shoot well though.
Can this cause any potential issues? Anything a drop tube can help with?
 

nhyrum

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Best way to find out is load a few and give them a few weeks. You will want to run a little more neck tension. Then maybe save one and have it be the last round in a mag, when you get to it, measure it to see if the bullet has moved. That's the best way I can think of to be certain.

But, if your powder is to the bottom of the neck just after the drop, adding a longer drop tube can help the powder settle, as can tapping the case/using an electric toothbrush on it. With that settling, you should have plenty of room. I've had more compressed loads than that. I do believe that there are a few powders that don't compress well (I'm certain there's a few that don't)

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Lawnboi

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A drop tube funnel is a cheap experiment. Forster makes one that’s less than 20 bucks. I use it for 223, little crunch with the funnel, lots of crunch without.
 

rayporter

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i have found that if the powder is going to push the bullet out it will be soon. usually in the first hour and certainly the first day. after a week that bullet aint movin easily, unless you have very little of it in the neck and can pull it out with your fingers.

drop tubes work if you pour slowly. if you cant pour slow at least stop pouring 3 or 4 times and let the powder settle. this even works pretty well with only a funnel.
 

JRMiller

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Assuming its still a safe load, i use an eletric toothbruth to gently vibrate the powder down in the case before seating the bullet.
Physicaly you’ll know when its too compressed if your CBTO starts to wander when seating bullets
Again, assuming safe loads only
 

OXN939

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I load for the 25wssm and have a super compressed load I use. I actually cant seat bullets until i tap the case a bunch of times to settle the powder! Never had an issue though

Gonna throw a newb question out there. Doesn't compressing powder to the point you have to do this make your load prone to pressure spikes?
 

morgaj1

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I ran into similar issues with my Tikka 300 WM when loading AB's and H1000. 2 things helped - Fire-formed cases and the Forster drop tube.
 
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I used an old aluminum arrow shaft for a drop tube when loading black powder 45-70 loads with 535 gr cast lead bullets. Worked very well. In your case an 18-16 shaft should fit in a .30 caliber case neck (should be about .28" OD) if you can find one to cut off the insert and nock end swage. Use your powder funnel to dump the powder in the top and have your primed case below with the arrow shaft drop tube just inside the case mouth.
 
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Gonna throw a newb question out there. Doesn't compressing powder to the point you have to do this make your load prone to pressure spikes?

No, not really. Pressure spikes happen when the case itself is compromised, such as getting wet. Then, you will see significant pressure spikes since the chamber is essentially smaller and the pressure has to go somewhere, spike it is.
 
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Best way to find out is load a few and give them a few weeks. You will want to run a little more neck tension. Then maybe save one and have it be the last round in a mag, when you get to it, measure it to see if the bullet has moved. That's the best way I can think of to be certain.

But, if your powder is to the bottom of the neck just after the drop, adding a longer drop tube can help the powder settle, as can tapping the case/using an electric toothbrush on it. With that settling, you should have plenty of room. I've had more compressed loads than that. I do believe that there are a few powders that don't compress well (I'm certain there's a few that don't)

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I think that if one increases neck tension, they decrease accuracy. The release of the bullet is less consistent as you are straining the brass. That has been my experience. My most accurate rounds are with minimal neck tension.

But vibrating the powder does assist in its settling and could avoid the compressing of the powder. The OP might benefit from getting software, such as Quickload, which will help with this situation.

My advice, get a different powder that is better tuned to this rifle/bullet/case. The RL series is not a very stable powder as it is not double based and is prone to pressure spikes due to difference in temperature. If you ever have to shoot that thing on a hot day, please be careful.
 

rayporter

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some powders like a lot of neck tension and some dont. VV133 is an example that likes lots of neck tension.
it is frequently loaded to the point of pushing the bullet out. long drop tubes and toothbrushes are used to get as much in the case as possible. but there is a point of no returns on the neck tension where the bullet will be pushed out. you can constrict the neck ten thou and only get so much tension. there is a limit.

most world record groups are held by VV133

you will need to test your powder to find what it likes [or know some one who has tested it] but even then every rifle is different and his results may not fit yours.

something to consider:
how many times did you ever pull a bullet that had been seated for several months? did you ever have to crack them loose by seating them 2 thou deeper thereby braking the 'weld'? that weld can be pretty solid even if you started out with very little tension. i never tried to measure the weld resistance but i would venture to guess it is the same for all bullets, no matter the neck tension you started with.
 
OP
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I think that if one increases neck tension, they decrease accuracy. The release of the bullet is less consistent as you are straining the brass. That has been my experience. My most accurate rounds are with minimal neck tension.

But vibrating the powder does assist in its settling and could avoid the compressing of the powder. The OP might benefit from getting software, such as Quickload, which will help with this situation.

My advice, get a different powder that is better tuned to this rifle/bullet/case. The RL series is not a very stable powder as it is not double based and is prone to pressure spikes due to difference in temperature. If you ever have to shoot that thing on a hot day, please be careful.
Several newer RL powders (23 included) are extremely temp stable. More so than Hodgdon powders once considered the benchmark.

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MeatBuck

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Say a load starts to get compressed at 46.5g when loading for a pressure string. Would you stop there or keep going up to 47g and 47.5g?
(More specifically rl-16 in a .243win.)
 

nhyrum

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I'd creep up on it, watching for pressure. .1-.2 grains at a time.

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MeatBuck

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Was actually compressed at 46.1g. Would going up by a grain to 46.5g be too far for a compressed load or Should I just use the shoot and see method?
(Lapua brass and mag primers, not jammed)
 
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