Muzzle Velocity for Reloads

Varmit

Varmit

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A chrony is next on my list but I don't have access to one right now. Was wondering if it is normal to get higher MV out of reloads? It seems to me that pre-rolled ammo must be a bit on the conservative side to accommodate all the differences in firearms out there and to avoid lawsuits and keep everything safe.

For instance my current load is 57gr H4350 for a 165 grain nosler bullet, (24 inch barrel, model 70 Win) which is a typical load for the 30-06. Just wondering if I am gaining any velocity over factory stuff? I always thought higher MV was one of the benefits of reloading but it seems that from what I've read guys get about the same MV as what is published for factory loads.

Just trying to learn as much as I can about reloading.
 
Velocity can usually be increased with reloading. To a point.

But the real true advantage is that you can load ammunition that is finely tuned to your individual rifles needs.

Some like one powder and bullet combo. Another doesnt care much about what powder/bullet combo you give it, it may just like all bullets seated to within .010"-.020" of the lands.

The challenge is to find what each rifle likes, and what it likes "BEST".
 
Remember this: 5% higher muzzle velocity equals 10% higher maximum pressure!

Example:
Safe 308 Win 180gr Accubond at 2700fps at 58,000 PSI
Hot 308 win 180gr Accubond at 2800fps at 62,000 PSI

In the above example, the safety margin (4000-5000 PSI) was sacrificed for an extra 100fps.
This extra velocity translates into an extra 30-40 yards of effective range.

Conclusions: go for safety, accuracy and use a more potent cartridge or select better bullet if you're looking for a significantly improved performance.

Alex
 
Varmit; At 57 grains of H4350 behind a 165 grain bullet, it is unlikely that you are exceeding factory ballistics by any substantial amount.

57 grains of that powder is my go-to 180 grain load in one of my '06 rifles, and produces 2850 fps in a 24" barrel.
The 165 will likely be about the same speed, or very slightly faster, and reflect factory loadings.

I expect to reach 2950 [give or take 25 fps] with a 165 grain bullet in the '06 with a 24" barrel, but H4350 may/may not be the powder to do it.

Only careful load development and a chronograph will give you the facts.

Regards, Eagleye.
 
There are elements of truth to your assumptions. A manufacturer does not load conservative, he loads appropriately. When he makes 45-70 he does not know if it is going in a vintage trap door or a new marlin. So he loads at trap door pressure, so it will be safe in everything.

For 30-06 he loads for the velocity they set for this caliber, years ago. With modern powders this is easy to do at moderate pressures. You can use the best powder for your bullet and get a bit more velocity than the factory actually delivers. Note that whet their ammo actually does vs what they say the velocity is - is two different things.
 
AlexF said:
Remember this: 5% higher muzzle velocity equals 10% higher maximum pressure!

Example:
Safe 308 Win 180gr Accubond at 2700fps at 58,000 PSI
Hot 308 win 180gr Accubond at 2800fps at 62,000 PSI

In the above example, the safety margin (4000-5000 PSI) was sacrificed for an extra 100fps.
This extra velocity translates into an extra 30-40 yards of effective range.

Conclusions: go for safety, accuracy and use a more potent cartridge or select better bullet if you're looking for a significantly improved performance.

Alex
Click to expand...

Published pressures are given as MAP. Maximum average pressure. There many reasons for stopping at a certain level, like the highest maximum pressure of the test batch, extremes of high and low and complicated statistical calculations that show that basically all of it should be safe if they quit at a certain level.If they quit at 55,000 psi instead of 60,000 its probably because they had to, not because they are nice guys.

A pressure tested and published load at 60,000 psi is given with the same degree of confidence of being safe as one from the same source that only averages 55,000. That's assuming that they aren't loading to a nominal velocity, or quit because the case was full.
 
As another poster on here stated, some chamberings are purposely kept to lower pressure
levels to assure safety in older, less robust actions.

Typical examples are the 45-70, the 7x57, and even the venerable 30-06.
Often, loading can improve the ballistics of these by a small margin. [the 45-70 can be improved significantly in the #1 & 3 Rugers]

This does not mean we should be trying to make a 300 Mag out of our 30-06, or a 7mm Mag out of a 7x57.
Being sensible with these chamberings demands that we use caution, and stop at reasonable levels.

I remember one poster a number of years ago, boasting about his 29" barrelled 30-06 delivering 3050 with a 180 grain bullet...good grief!!
It would have been interesting to have a transducer on that rifle to see what sort of pressures he was running.

The fact that some seem to get away with this foolishness is testament to the strength of modern actions and the quality of the brass.
However, sooner or later, this practice will bring trouble, and that may be serious trouble. Best to be safe.

Regards, Eagleye.
 
My M96 Swede Mauser can only shoot about 1 MOA with factory ammo. Handloads I have shot 1/2 MOA groups but average closer to 3/4 MOA.
6.5x55mm Swede ammo is about $1.25/round. My handloads are about half that.
These are the true advantages of handloading.

As said above, handloading can also increase the MV of some cartridges that are loaded on the lower side due to age. One not mentioned that is loaded quite weakly is .303 British. Also some factory .303 Brit ammo comes with quite different sized bullets. One guy I saw shooting factory Remington 303 ammo had 4/5 shots tumbling and keyholeing on the paper. He had a good condition Enfield with good rifling but it just had a looser bore as a result of sloppier wartime production standards. My No.1 Mk.3 keyholes with .3105" or smaller. Best accuracy I need .313" or larger. So for older guns, milsurp guns, or guns with worn rifling handloading can bring them back up to par or in some cases turn them from wall hangers to meat harvesters.
 
As mentioned, you may gain speed, but the most accurate loads are usually under max or factory loads, but not all the time!
X2 of change the bullet if you want speed - try any of the 150 mono bullets for velocity, Barnes, Bergers, Nosler tips, GMX to name a few.
 
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