how to SLOW a bullet down

[crustyrusty]

I just put together some really nice 110 gr 280 Remington loads.. moving at about 3100 fps recoil not so bad so I downloaded it a little more recoil seemed to be the same the common denominator is that a somewhat faster burning powder is used with lighter bullets. my question is is it possible to do just the opposite? use the absolute slowest powder with like 85-90% case fill with these light bullets? like hodgdon 50BMG? has any one done this before? I like the Idea of a 110 bullet to plink with that does about 2400-2500 fps out of my 280 until my 7mm BR comes online so any suggestions either way to achieve this (I just read the burn rate chart and 50 bmg is too slow.... but there are other contenders) what if I take IMR 4350 and reduce the start load by 20% will that get me into trouble? will it cause a pressure spike? the main reason for all of this is I just love shooting but with my 280 using full power loads I jerk the trigger, close my eyes, jump a little, flinch just about everything wrong to get good groups. now with my .223 rem I do just fine... so If i can reduce the recoil and rifle bounce that would be a major win for me... now when I hunt with my 280 nothing bothers me go figure

 

[mmcu]

H4895. See attached for reduced load information.

 

[Ned Ludd]

There are at least a couple obvious options: 1) use a different powder; 2) use a smaller charge weight of the same powder.

The issues with the first option are that if you go with a powder that is too slow-burning, it is likely that not all the powder will have combusted before the bullet exits the bore. Thus you will be effectively wasting a certain amount of it. In addition, many of the slower-burning powders have larger kernels than their faster-burning counterparts. This can sometimes be detrimental to consistent velocity with smaller cartridges due to less precise powder weight measurement.

The main issue with the second option is that going too low on the case fill can create other undesirable problems. The real question there is how low can you go before this becomes noticeable? In other words, can you drop the charge weight with the same powder low enough to achieve your desired velocity window without dropping the case fill ratio below a certain point? To be honest, I'm not really sure how low you can reliably go on the case fill ratio before [too] low pressure loads become a problem.

Finally, no matter which powder and/or burn rate you choose, it will have to be tuned in using standard load development approaches. You may find that a powder that is way too fast or too slow will not give you the desired results (i.e. not tune in well) in the reduced velocity range you're after. IMO - the place to start would be to look at powders with a different burn rate that still fall within the approximate region of a burn rate chart as what you have been using. Along the same line, not all powders are created equal, regardless of whther they have similar burn rates. For example, H4895 and Varget are fairly close with regard to burn rates, H4895 being slightly faster than Varget. However, H4895 is also a slightly higher energy powder than Varget, so you typically will see greater velocities by about 20-30 fps at a given accuracy node with H4895. Single base powders are often lower energy as compared to double base powders. If you have access to QuickLoad, take a look at the heat of explosion/potential values, as well as the the propellant solid density values for different powders. For powders that are fairly close in terms of their burn rates, a decrease in either one (or both) of these values should mean that a given powder will tune in slightly slower relative to one with higher values. The bottom line is that you may have to play around with several factors to get where you want to be. Nonetheless, it should be an achievable goal.

 

[crustyrusty]

yeah I noticed that when I was on hodgdons data site they had a listing using H1000 powder with a 150gr bullet and a start load of 2550 fps. that got me thinking so I looked at the IMR 4350 load for the 120gr and using the calculator finding a 20% reduction got me to where I want to be 2450ish... so I tried to to find quickload but to no avail I landed in the U.K.... I am worried about too low case pressures as well, and I am worried of unburned powder being expelled out the barrel. so the search goes on and thanks for the info on h4895

 

[Curmudgeon]

Get better ear plugs then add a muzzle brake. If you have decided to flinch a few hundred feet per second won't make a difference. Take the brake off when you go hunting. Cheers

 

[crustyrusty]

I just looked at MMCU posting to look at h4895 reduced rifle loads.... that's really cool!!! they don't list the 280 there but they do list the 270 with the same bullet weight I can use that as a guide cant I? that is exactly what I want to shoot

 

[ebb]

I used H4895 to load some 308 win for a neighbor that is getting older. When I looked up the data IIRC you can load 60% of a max H4895 load.

 

[mmcu]

I just looked at MMCU posting to look at h4895 reduced rifle loads.... that's really cool!!! they don't list the 280 there but they do list the 270 with the same bullet weight I can use that as a guide cant I? that is exactly what I want to shoot

To determine a load for your 280, please re-read the second paragraph of the Hodgdon document that I attached earlier in this thread. It states "To create this type of target and plinking loads, we recommend our 60% rule with H4895: Refer to our latest reloading manual or the Reloading Data Center found on this website; take the maximum H4895 charge listed for any given cartridge and multiply it by 60%.".

There is no reason to extrapolate data from another cartridge. Simply determine the maximum charge of H4895 for your cartridge / bullet weight combination and multiply by 0.6 for your starting load.

Please ask questions if you are not 100% sure on how to proceed.

 

[MGYSGT]

How to slow a bullet down. Put a Commie in front of it.

 

[crustyrusty]

i went to hodgdon web page and looked at there load data for the 280 Rem max load and then multiplied it by .6 and the number that I came up with is 29.4 well short of other examples in that chart for smaller cases... dont make sense

 

[crustyrusty]

the max load in question is for a 115gr bullet with 49 gr of h4895...

 

[crustyrusty]

ok so I called Hodgdon and got the poop from the tech guy there,, and yes the number I came up with IS correct... however it is the floor and not meant to be gone under,, but can be worked up from there as need be and he said that this formula is good with any bullet weight where H4895 is listed

 

[DocDoc]

The other problem with slow powders and too little powder in the case, is that they can occasionally have very high pressure events that can damage the rifle. A number of manuals warn to not go below starting loads with some slow powders.

 

[TAJ45]

May want to consider a filler. Tissue, cow or? You don't want the primer flame to flash over a long powder surface. A long cartridge like the .280 is very susceptible.

 

[dstoenner]

May want to consider a filler. Tissue, cow or? You don't want the primer flame to flash over a long powder surface. A long cartridge like the .280 is very susceptible.

I use a product called pufflon. It is a ballistic filler. Works great except it is dirty when using it in a semi automatic. My 1903a3 bolt is not an issue

David

 

[crustyrusty]

ok I used the 60% rule with h4895, worked out to 29.5gr as the bottom charge.. so I loaded 5 rounds each of 30gr, 32gr, 34gr and 36gr. they all shot really well.. i did notice an occasional muzzle flash but not to bad,, recoil was modest.. really couldn't tell the difference between the 30gr load from the 36gr load. the bullet was 120 gr hornady sp flat base. accuracy was really amazing really i got 3 1inch 5 shot groups out of the deal...

 

[snert]

welcome to the world of reduced loads....where accuracy is often a wonderful byproduct. i love the 222 with a reduced load for tree squirrels.

 

[crustyrusty]

My new favorite loads are h4985 for both my 280 Remington and my .223 Remington 100gr 280 rem at 2000fps and .223 rem 55gr at 1800fps

 

[MihiT]

I consider the "underloading" thing to be a myth.(On acount of exactly zero evidence)

Do a backwards-ladder until you hit the speed you want.

 

[mauser284]

I just put together some really nice 110 gr 280 Remington loads.. moving at about 3100 fps recoil not so bad so I downloaded it a little more recoil seemed to be the same the common denominator is that a somewhat faster burning powder is used with lighter bullets. my question is is it possible to do just the opposite? use the absolute slowest powder with like 85-90% case fill with these light bullets? like hodgdon 50BMG? has any one done this before? I like the Idea of a 110 bullet to plink with that does about 2400-2500 fps out of my 280 until my 7mm BR comes online so any suggestions either way to achieve this (I just read the burn rate chart and 50 bmg is too slow.... but there are other contenders) what if I take IMR 4350 and reduce the start load by 20% will that get me into trouble? will it cause a pressure spike? the main reason for all of this is I just love shooting but with my 280 using full power loads I jerk the trigger, close my eyes, jump a little, flinch just about everything wrong to get good groups. now with my .223 rem I do just fine... so If i can reduce the recoil and rifle bounce that would be a major win for me... now when I hunt with my 280 nothing bothers me go figure

Trail Boss might be doable. Just make sure the bullet actually makes it out of the barrel. People joke about filling a rifle case to the top with it and stuffing a bullet in it and still having no recoil! Sometimes people call Trail Boss "The Doughnut Powder".

If you interpolate between 7-08 and 7RM that get's you going. IMR tells you to measure the amount of bullet depth into the case and your maxload is to fill i to that point in the case according to IMR's instruction for cartridges not listed in their data! All joking aside do not compress trail boss you you will change the burn rate I am sure. I guarantee you will get slow gently recoil with IMR TrailBoss!