Barrel time and factory ammo

[jpmimproved]

Given that QuickLoads and barrel time theory seems to be showing a lot of promise, does anyone foresee ammo companies manufacturing ammunition for particular length barrels? For example, are manufacturers making 6.5 creedmoor ammo for optimal performance in a 22" or 24" barrel since that is what you normally see in factory rifles? Will there be a day where when you go to the store you buy ammunition based on your barrel?

 

[DaveTooley]

no Quickload is a guide just as loading manuals are a guide. The target tells all.

 

[MrBottleneck]

Will there be a day where when you go to the store you buy ammunition based on your barrel?

Well, asking it that way yes as they already do. Its all made that way. Your barrel is Caliber specific.

But, I know you left out the word "length". So, with that said.
I would say not. The manufacturers are making ammo that fit a broad spectrum and are made to work in mutiple like chambered rifles. It would be to costly and there are to many barrel lengths/OBT to cover.

Holy great scott could you just imagine a gun shop loaded to the walls with every caliber made broken down to cover every available OBT. Wow that would be a lot of ammo.

 

[dcali]

No. Optimal barrel time depends on the the whole rifle system (not just barrel length) and you can't make one size fits all ammunition for that reason. If they could they would. You might also be surprised by how much variation in charge weight there is in factory ammo. This is why we reload.

 

[seymour fish]

Well, asking it that way yes as they already do. Its all made that way. Your barrel is Caliber specific.

But, I know you left out the word "length". So, with that said.
I would say not. The manufacturers are making ammo that fit a broad spectrum and are made to work in mutiple like chambered rifles. It would be to costly and there are to many barrel lengths/OBT to cover.

Holy great scott could you just imagine a gun shop loaded to the walls with every caliber made broken down to cover every available OBT. Wow that would be a lot of ammo.

Fed gmmm works in 308 reasonably well at bbl lengths from 16 on out. Do they know something along this line ?

 

[DaveTooley]

Go to the site below, page 306 of SAAMI specs for rifle cartridges. Anyone can use this information and there is a lot on there site. I suggest you read and learn. This is the page for pressure and velocity barrels for the 308 Win. It provides chamber dimensions and transducer port location to measure chamber pressure which is all their main concerned. Can they manage the distance to max pressure while the bullet travels down the barrel, yes to a degree. A slightly faster powder will spike sooner and a slightly slower powder will spike further down the barrel but the changes are very subtle. Pressure relates directly to velocity and there are standards they have to meet for pressure and velocity standards that are driven by the market place. Look on page 19 for CUP and page 31 for transducer measurements of that same document for the pressure standards for various bullet weights. If the link below doesn't get you directly to the rifle section use
WWW.SAAMI.Org
and 3 clicks later you'll be there.

http://saami.org/specifications_and...ns/download/Z299-4_ANSI-SAAMI_CFR.pdf#page=13

 

[ragsflh]

thats why we roll your own

 

[normmatzen]

The average shooter buying ammunition at the local Walmart is not shooting Bench Rest or Sillouette, he is shooting game. Bench Rest/F Class use M.O.A and hunters use M.O.D, which is minute of deer and 1-2 MOA is fine for that and precision shooters will re-load for way more accuracy, like 0.25-0.5 MOA.

 

[mr45man]

might also be surprised by how much variation in charge weight there is in factory ammo. This is why we reload.

I have pulled some down just to check how much variation there is. It's a lot, 1 grain + or- is not unusual. I'm surprised some of it shoots as good as it does .

 

[Ned Ludd]

Given that QuickLoads and barrel time theory seems to be showing a lot of promise, does anyone foresee ammo companies manufacturing ammunition for particular length barrels? For example, are manufacturers making 6.5 creedmoor ammo for optimal performance in a 22" or 24" barrel since that is what you normally see in factory rifles? Will there be a day where when you go to the store you buy ammunition based on your barrel?

Barrel length-specific ammunition seems rather unlikely to me. It's about all commercial ammunition companies can do to keep up with current demand for just a single variant of any ammo they produce. In order to post reasonable sales, commercial ammunition needs to shoot reasonably well out of a wide range of different types of rifles. Even with only one barrel length and a single bullet in mind, trying to develop a load that produced a specific and narrow barrel occupancy time range for a wide variety of different rifles with varying freebore lengths would probably be an exercise in futility. Moreover, barrel length-specific load variants would increase costs, limit (or even decrease) supply, and probably have a neglible effect on overall sales of any given brand.