Pressure Signs with starting loads

R

russm86

New member
I'm new to Hammer bullets, but have about 15 years maybe more reloading experience and have a pretty good idea of what I'm doing generally and no stranger to mono bullets in general. Have developed numerous loads with minimal published data etc or using quickload and so on and never had any issues. Now I seem to be having issues with these hammer bullets. I have 2 different rifles, a 7mm PRC and 6.5 Creed, using different powders and obviously different calibre & weight of bullets, the only similarity being both using hammer hunter bullets, and both seem to be showing pressure signs (flattened primers, ejector marks, and sticky bolt) nearly right from the suggested starting load data taken from Hammer bullets website.

In the 6.5 Creed with 110gr Hammer Hunters, I tried the suggested CFE223 load from hammer website load data and I was 200fps slower than stated for starting load and bolt was sticky right off the bat even though I wasn't seeing ejector marks or flattened primers. Now, the 20" barrel on these rifles MAY account for this but still seems like a large difference. I will add this is a previously "unproven" rifle but is factory Howa superlite and haven't seen/heard any issues with them. Since I wasn't seeing the pressure signs on the brass I did creep up a couple more grains but bolt lift just got progressively stickier so called it quits.

Then with the 7mm PRC, which is a proven rifle with factory ammo, I tried the 155gr hammer hunters. I did have to extrapolate the load data from Hammer Hunter load data website as they only have 150gr (64gr start with 7828SSC) and 160gr (62gr start with 7828SSC) shock hammers listed, not this exact bullet but figured I'd fit between the 2. I was going to start with 63gr 7828SSC but ended up starting at 64gr as I'm seated out quite a bit further than the suggested loads (leaving more case volume) but still lots of jump to the lands. I was seeing minor ejector marks right off the bat with the starting load but no sticky bolt so crept up a couple more grains again and on the 4th shot (.5 gr increments) I got definite extractor and ejector marks as well as sticky bolt lift. I was pretty close to the suggested starting velocity from the load data though with my starting load.

Both were crimped as suggested with Lee FCD. I've read, hammer bullets are supposed to have less pressure, what am I missing? Am I just unlucky with my rifles not liking my 1st 2 tries at Hammer bullets? Seems odd to have over pressures signs in 2 different rifles though right off the bat. I don't tend to believe in coincidence.

Load data (obtained here https://hammerbullets.com/load-data/) as follows:
6.5 Creed - 110gr Hammer Hunters, new/unfired Sig brass, S&B LR primers, CFE223 (started at 42gr which yielded 2922fps), 2.620" OAL

7mm PRC - 155gr Hammer Hunters, new/unfired Peterson brass, CCI 250 Magnum LR primers, IMR 7828SSC (started at 64gr which yielded 3076fps), 3.310" OAL
 
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russm86 said:
I'm new to Hammer bullets, but have about 15 years maybe more reloading experience and have a pretty good idea of what I'm doing generally and no stranger to mono bullets in general. Have developed numerous loads with minimal published data etc or using quickload and so on and never had any issues. Now I seem to be having issues with these hammer bullets. I have 2 different rifles, a 7mm PRC and 6.5 Creed, using different powders and obviously different calibre & weight of bullets, the only similarity being both using hammer hunter bullets, and both seem to be showing pressure signs (flattened primers, ejector marks, and sticky bolt) nearly right from the suggested starting load data taken from Hammer bullets website.

In the 6.5 Creed with 110gr Hammer Hunters, I tried the suggested CFE223 load from hammer website load data and I was 200fps slower than stated for starting load and bolt was sticky right off the bat even though I wasn't seeing ejector marks or flattened primers. Now, the 20" barrel on these rifles MAY account for this but still seems like a large difference. I will add this is a previously "unproven" rifle but is factory Howa superlite and haven't seen/heard any issues with them. Since I wasn't seeing the pressure signs on the brass I did creep up a couple more grains but bolt lift just got progressively stickier so called it quits.

Then with the 7mm PRC, which is a proven rifle with factory ammo, I tried the 155gr hammer hunters. I did have to extrapolate the load data from Hammer Hunter load data website as they only have 150gr (64gr start with 7828SSC) and 160gr (62gr start with 7828SSC) shock hammers listed, not this exact bullet but figured I'd fit between the 2. I was going to start with 63gr 7828SSC but ended up starting at 64gr as I'm seated out quite a bit further than the suggested loads (leaving more case volume) but still lots of jump to the lands. I was seeing minor ejector marks right off the bat with the starting load but no sticky bolt so crept up a couple more grains again and on the 4th shot (.5 gr increments) I got definite extractor and ejector marks as well as sticky bolt lift. I was pretty close to the suggested starting velocity from the load data though with my starting load.

Both were crimped as suggested with Lee FCD. I've read, hammer bullets are supposed to have less pressure, what am I missing? Am I just unlucky with my rifles not liking my 1st 2 tries at Hammer bullets? Seems odd to have over pressures signs in 2 different rifles though right off the bat. I don't tend to believe in coincidence.

Load data (obtained here https://hammerbullets.com/load-data/) as follows:
6.5 Creed - 110gr Hammer Hunters, new/unfired Sig brass, S&B LR primers, CFE223 (started at 42gr which yielded 2922fps), 2.620" OAL

7mm PRC - 155gr Hammer Hunters, new/unfired Peterson brass, CCI 250 Magnum LR primers, IMR 7828SSC (started at 64gr which yielded 3076fps), 3.310" OAL
Click to expand...
Can I ask what brand rifle? I have a Savage and every primer is flat. I get a heavy bolt lift on an empty gun.
 
russm86 said:
I'm new to Hammer bullets, but have about 15 years maybe more reloading experience and have a pretty good idea of what I'm doing generally and no stranger to mono bullets in general. Have developed numerous loads with minimal published data etc or using quickload and so on and never had any issues. Now I seem to be having issues with these hammer bullets. I have 2 different rifles, a 7mm PRC and 6.5 Creed, using different powders and obviously different calibre & weight of bullets, the only similarity being both using hammer hunter bullets, and both seem to be showing pressure signs (flattened primers, ejector marks, and sticky bolt) nearly right from the suggested starting load data taken from Hammer bullets website.

In the 6.5 Creed with 110gr Hammer Hunters, I tried the suggested CFE223 load from hammer website load data and I was 200fps slower than stated for starting load and bolt was sticky right off the bat even though I wasn't seeing ejector marks or flattened primers. Now, the 20" barrel on these rifles MAY account for this but still seems like a large difference. I will add this is a previously "unproven" rifle but is factory Howa superlite and haven't seen/heard any issues with them. Since I wasn't seeing the pressure signs on the brass I did creep up a couple more grains but bolt lift just got progressively stickier so called it quits.

Then with the 7mm PRC, which is a proven rifle with factory ammo, I tried the 155gr hammer hunters. I did have to extrapolate the load data from Hammer Hunter load data website as they only have 150gr (64gr start with 7828SSC) and 160gr (62gr start with 7828SSC) shock hammers listed, not this exact bullet but figured I'd fit between the 2. I was going to start with 63gr 7828SSC but ended up starting at 64gr as I'm seated out quite a bit further than the suggested loads (leaving more case volume) but still lots of jump to the lands. I was seeing minor ejector marks right off the bat with the starting load but no sticky bolt so crept up a couple more grains again and on the 4th shot (.5 gr increments) I got definite extractor and ejector marks as well as sticky bolt lift. I was pretty close to the suggested starting velocity from the load data though with my starting load.

Both were crimped as suggested with Lee FCD. I've read, hammer bullets are supposed to have less pressure, what am I missing? Am I just unlucky with my rifles not liking my 1st 2 tries at Hammer bullets? Seems odd to have over pressures signs in 2 different rifles though right off the bat. I don't tend to believe in coincidence.

Load data (obtained here https://hammerbullets.com/load-data/) as follows:
6.5 Creed - 110gr Hammer Hunters, new/unfired Sig brass, S&B LR primers, CFE223 (started at 42gr which yielded 2922fps), 2.620" OAL

7mm PRC - 155gr Hammer Hunters, new/unfired Peterson brass, CCI 250 Magnum LR primers, IMR 7828SSC (started at 64gr which yielded 3076fps), 3.310" OAL
Click to expand...
For the 7PRC, which I am loading 162gr for, the Hornady load data on their 160gr CX copper gives a 64gr max load for 7828ssc, which is less than their max load for a 175gr ELD-X. For lead bullets in the 162-166gr range, they max at 66.3gr. I'm getting overpressure signs at smaller charges with other powders with the 162gr Hammer HHTs, but I'm getting 200-250 more fps with acceptable loads. I haven't tried 7828ssc yet though. What;s your rifle and barrel length?
 
The 6.5creed is a factory howa superlite with 20" barrel.

The 7PRC is a custom built on a slabbed, skeletonized, and fluted weatherby vanguard stainless action with a McMillan ks mountain stock and 24" benchmark barrel.

I'll have to do some more digging on load data for comparable bullet weights, wondering if the data in the link I gave above is really hot or has some errors?
 
russm86 said:
The 6.5creed is a factory howa superlite with 20" barrel.

The 7PRC is a custom built on a slabbed, skeletonized, and fluted weatherby vanguard stainless action with a McMillan ks mountain stock and 24" benchmark barrel.

I'll have to do some more digging on load data for comparable bullet weights, wondering if the data in the link I gave above is really hot or has some errors?
Click to expand...
Nice platforms!

The COAL for the 160gr Shock Hammer in the load data you linked is most likely much shorter than your loads, and less jump may lead to a more aggressive pressure curve. I started long too, and once I seated deeper, overpressure signs went away for the same charge weight. 50 thou deeper gave me about 1/2 grain of relief.
 
@russm86 ,

Thanks for your post, and sorry to hear you're having difficulties. Your experience is not the norm with Hammers.
Several very knowledgeable folks are on the Forum and all would like to help!

You stated you're experienced at reloading, so please don't take this as offensive, but we don't really have enough information to help you yet.
At the risk of pointing out the obvious, let's start at the beginning and go through the process for developing a load.

First, you need to measure your chamber and find out what "jam" length is in your chamber/barrel with a given bullet. Once you find the rifling, seat your bullets .020 off "jam" for starters. You may need to go to much more jump, but that's a good place to start. You can't just follow the listed OAL from others' loads without first checking your chamber.

For suggested load data, I recommend going to Reloading on this Forum and look at the Hammer Hunter Load Data spreadsheets. I reserve any comments on the data listed on the HammerBullets.com location. Yours is not the first to question them.

In the load data posted on this Forum, there is a load listed for the 155HH in the 7 PRC, for both H1000 and H 4831. 7828 falls in between these two in burn rate, so there should be a good load in there somewhere. For comparison, there is also load data for the 7 Sherman Short and 7 SAUM. Both of these cartridges are in a similar capacity range to the PRC and can give you indications of charge ranges and velocities to expect. Use your reloading knowledge to extrapolate charge ranges and results.

Also, the bullet nose profiles vary quite a bit between types of Hammer Bullets. Some, like the Shock Hammers and Lever Hammers have a more blunt/short "nose" profile. Hammer Hunters and Absolutes have a much longer, more sleek nose. These design profiles can have a Very Large bearing on bullet seating depth. This is why measuring your chamber with the bullet you plan to load is so important. Your seating depth will likely be quite different from bullet style to bullet style.

For the 6.5 CM, there are 3 pages of load data for the 110 HH bullet on this Forum.
Varget is the most popular powder, OAL averages around 2.700 in most chambers, and a starting load of 39.0 gr typically yields around 2900 fps. There is also data on H 4350, IMR 4166, IMR 4064 and StaBall 6.5.

Revisit your loading practices and give us some data to work with.

Regards.
 
russm86 said:
Both were crimped as suggested with Lee FCD. I've read, hammer bullets are supposed to have less pressure, what am I missing? Am I just unlucky with my rifles not liking my 1st 2 tries at Hammer bullets? Seems odd to have over pressures signs in 2 different rifles though right off the bat. I don't tend to believe in coincidence.

Load data (obtained here https://hammerbullets.com/load-data/) as follows:
6.5 Creed - 110gr Hammer Hunters, new/unfired Sig brass, S&B LR primers, CFE223 (started at 42gr which yielded 2922fps), 2.620" OAL
Click to expand...
I've only had one Howa, and it was out of tolerances on every thing we could measure. Performed as expected. Gave it to a youngster to trade in on something else.

Never shot a PRC of any kind, but lots of reports regarding sticky extraction. Some suggesting reamer, or die alteration.

Sometimes statistics cluster (not coincidence).
 
I would recommend starting your seating depth further than 0.02 if you don’t have precision tools. Hornady is not precision enough to rely on when dealing with 20 thousandths of an inch. Find jam ( or what you believe to be jam) and then seat the bullet deeper than you think you would like. Hammers have not been sensitive to jump.

I have seen early pressure with hammers twice (once with me and once with a buddy). Both times it’s because we were to close to the lands /jam.
 
russm86 said:
I'm new to Hammer bullets, but have about 15 years maybe more reloading experience and have a pretty good idea of what I'm doing generally and no stranger to mono bullets in general. Have developed numerous loads with minimal published data etc or using quickload and so on and never had any issues. Now I seem to be having issues with these hammer bullets. I have 2 different rifles, a 7mm PRC and 6.5 Creed, using different powders and obviously different calibre & weight of bullets, the only similarity being both using hammer hunter bullets, and both seem to be showing pressure signs (flattened primers, ejector marks, and sticky bolt) nearly right from the suggested starting load data taken from Hammer bullets website.

In the 6.5 Creed with 110gr Hammer Hunters, I tried the suggested CFE223 load from hammer website load data and I was 200fps slower than stated for starting load and bolt was sticky right off the bat even though I wasn't seeing ejector marks or flattened primers. Now, the 20" barrel on these rifles MAY account for this but still seems like a large difference. I will add this is a previously "unproven" rifle but is factory Howa superlite and haven't seen/heard any issues with them. Since I wasn't seeing the pressure signs on the brass I did creep up a couple more grains but bolt lift just got progressively stickier so called it quits.

Then with the 7mm PRC, which is a proven rifle with factory ammo, I tried the 155gr hammer hunters. I did have to extrapolate the load data from Hammer Hunter load data website as they only have 150gr (64gr start with 7828SSC) and 160gr (62gr start with 7828SSC) shock hammers listed, not this exact bullet but figured I'd fit between the 2. I was going to start with 63gr 7828SSC but ended up starting at 64gr as I'm seated out quite a bit further than the suggested loads (leaving more case volume) but still lots of jump to the lands. I was seeing minor ejector marks right off the bat with the starting load but no sticky bolt so crept up a couple more grains again and on the 4th shot (.5 gr increments) I got definite extractor and ejector marks as well as sticky bolt lift. I was pretty close to the suggested starting velocity from the load data though with my starting load.

Both were crimped as suggested with Lee FCD. I've read, hammer bullets are supposed to have less pressure, what am I missing? Am I just unlucky with my rifles not liking my 1st 2 tries at Hammer bullets? Seems odd to have over pressures signs in 2 different rifles though right off the bat. I don't tend to believe in coincidence.

Load data (obtained here https://hammerbullets.com/load-data/) as follows:
6.5 Creed - 110gr Hammer Hunters, new/unfired Sig brass, S&B LR primers, CFE223 (started at 42gr which yielded 2922fps), 2.620" OAL

7mm PRC - 155gr Hammer Hunters, new/unfired Peterson brass, CCI 250 Magnum LR primers, IMR 7828SSC (started at 64gr which yielded 3076fps), 3.310" OAL
Click to expand...
Let's work on the creed to start. If I'm understanding correctly you are seeing over pressure signs with low velocity? These two things generally don't go together. High pressure will generate high velocity. So we need to try and figure out what could be causing pressure signs on the brass without yielding velocity. I think there are couple of things that can show these signs. A loose chamber or too much head space will cause the brass to slam into the bolt face on ignition and give all the classic pressure signs of too hot a load. Brass or chamber that is not clean and dry can do the same. If there is sizing lube left on the brass or oil/ cleaning solvent left in the chamber this will allow the brass to slam on the chamber, because the brass doesn't get "traction" with the walls of the chamber.

We have seen premature pressure signs in some loads or particular cartridges when the ignition is too hot. This causes the powder to burn mostly in the chamber and not in the barrel. This comes from too hot of a primer. Like magnum vs large rifle primer. I call this phantom pressure. I personally generally use magnum primers but there are times that lr primers work better and yield the ability to run more powder with less pressure signs on the brass and higher velocity.

Does any of this make sense with what you are experiencing?
 
Steve Davis said:
Let's work on the creed to start. If I'm understanding correctly you are seeing over pressure signs with low velocity? These two things generally don't go together. High pressure will generate high velocity. So we need to try and figure out what could be causing pressure signs on the brass without yielding velocity. I think there are couple of things that can show these signs. A loose chamber or too much head space will cause the brass to slam into the bolt face on ignition and give all the classic pressure signs of too hot a load. Brass or chamber that is not clean and dry can do the same. If there is sizing lube left on the brass or oil/ cleaning solvent left in the chamber this will allow the brass to slam on the chamber, because the brass doesn't get "traction" with the walls of the chamber.

We have seen premature pressure signs in some loads or particular cartridges when the ignition is too hot. This causes the powder to burn mostly in the chamber and not in the barrel. This comes from too hot of a primer. Like magnum vs large rifle primer. I call this phantom pressure. I personally generally use magnum primers but there are times that lr primers work better and yield the ability to run more powder with less pressure signs on the brass and higher velocity.

Does any of this make sense with what you are experiencing?
Click to expand...
I can attest to the large chamber part. My A-bolt 280 REM cases were growing .005 to .007 and showing lots of ejector marks before I figured it out and started barely bumping the shoulder.
 
Another thing that I want to add to this discussion is that we intentionally state an overall cartridge length on our load data that is minimum possible oal for the bullet. We did this because there are so many different amounts of available free bore/throat depth out there that we felt it is most safe to list a min col. This is figured out be seating the bullet shoulder at the case mouth. The shoulder of the bullet is the point on the bullet where as you go along the ogive and it reaches full caliber in dia. Bullets seated deep and not engaging the lands is much safer than listing an oal that fits in most rifles but may be jammed in some. A jammed bullet is like being loaded an extra 4gr of powder. We always sugest finding where the bullet engages the lands and then backing off another 20 thou or seating to the capacity of the magazine (whichever is shorter) and use that as your starting or longest col. This method will make the listed start load even more mild but still a good spot to start.

I was really hoping that @russm86 would re-join the conversation here so we could figure out what is going on in his particular situation. I hate not figuring out the answer to the mystery.
 
Sorry, I was away for a couple days. So to answer a few questions, I always measure my chamber OAL with the specific bullet I'm using, I had read hammer bullets were not sensitive to seating depth so I seated them at 3.310" where my rifle was measuring 3.330" jammed/to the lands. That gave about .02" jump. I can increase jump but not sure .02" would be considered jam and would increase pressure considerably over say .05". The other reason I went .02 instead of .05 jump is because of where the bands landed on the case mouth. .02" seated flush on one of the bands. The other side of it is, if you start shrinking the volume of the case by seating deeper you can actually increase internal pressure within the case and cause spikes that way too, especially if you start compressing the load. Seating out deeper may increase bullet land contact/engraving pressure but decreases internal pressure (sometimes at the expense of velocity as well which needs to be made up for by adding more powder).

For the 6.5creed, my rifle would allow me to seat the bullet out far enough that it wouldn't even hold in the case mouth, measuring about 2.884" for jam, and i was seated to the recommended 2.620" giving about .260" of jump, so quite the opposite of the 7PRC. As i said, not really any consistency/common denominator between these 2 rifles other than the source of the load data and the bullet type itself.

This brings me to the next thing, the load data sourced from Hammer bullets website. After comparing against published load data from Hodgdon and a couple others, it appears that the load data suggested by Hammer's website for starting charge is at the max end of the data for all other published data. For instance the 6.5creed with CFE223, Hodgdon shows a 107gr lead core bullet (which will be substantially shorter as well as obviously slightly lighter) with a max charge of 41.5gr with 3076fps. The data from Hammer suggested start charge at 42gr with 3100fps and a max velocity of 3300fps, again with a heavier and much longer bullet. 7PRC I found similar, Hodgdon data for 150gr Etip showed 7828SSC with max charge 65gr at 3066fps, and 162gr eldx with max charge of 65.6gr at 3029fps. Hammer suggested start at 62-64gr (depending whether you used 160 or 150gr as 155 wasn't listed) at 3000-3050fps and max velocity of 3250fps.

I know some will say that published data from the big names is often "watered down" for liability and so on but I often find it close to top end for pressure, maybe getting .5gr to 1.5gr over depending on the rifle and seating depth and case volume etc. There's also no "free lunch" as far as pressure vs velocity. So I'm going to throw out the Hammer data and start over entirely with some other published loads, comparing to those user submitted loads in the PDF sheets that I didn't have access to originally.
 
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