So like a dummy I bought a box of 175grain deep curls to try in my 7mm Mag without checking the Speer manual. When I finally looked at the updated info it only lists 3 propellants for loading the 175 gr. and I don't have any of them. Has anyone tried working up any loads for the Deep Curls? Speer recommends using slow burning powders, can I try an IMR 4831? Is it slow enough of a powder and could I use the same load data as for let's say a Hornady btsp in 175 grain?
Speer Deep Curl bullets
- Thread starter Big Game
- Start date
The Hodgdon data site lists 12 powders from H, IMR, and Win lines for a 175gr bullet in a 7mm RM.
IMR4831 is one of them. 54.0 to 58.0 gr producing 2540 to 2710 fps (as always, take published velocities as guidelines only).
Their data is for a Nosler partition which is of similar enough construction (copper jacket, lead core) that the data can be interchanged at starting values.
I've always used this for interchanging load data from starting loads and it's always worked well. Data for bullets of different construction can be quite different as they can produce pressure differently. I segregate data for cup and core (copper jacket lead core), solid copper, and cast lead. Some argue against this method because things like ogive, bearing surface, jacket alloy or hardness, and other variables do change the velocity and pressure produced with the same bullet but in general, starting loads are quite a bit below max pressure so there is a healthy margin of error.
IMR4831 is one of them. 54.0 to 58.0 gr producing 2540 to 2710 fps (as always, take published velocities as guidelines only).
Their data is for a Nosler partition which is of similar enough construction (copper jacket, lead core) that the data can be interchanged at starting values.
I've always used this for interchanging load data from starting loads and it's always worked well. Data for bullets of different construction can be quite different as they can produce pressure differently. I segregate data for cup and core (copper jacket lead core), solid copper, and cast lead. Some argue against this method because things like ogive, bearing surface, jacket alloy or hardness, and other variables do change the velocity and pressure produced with the same bullet but in general, starting loads are quite a bit below max pressure so there is a healthy margin of error.
Thanks for the input. I figured I could use the 4831 but the bullet construction on the Deep Curls is different with the bullets being plated. I was worried about pressures since the Speer data calls for IMR7828 with this bullet.
Deep Curl bullets aren't plated; they're jacketed like any normal rifle bullet. They have a chemically bonded jacket to the core but it's still a conventional jacketed bullet.
Why would IMR4831 cause pressure problems? Stick to the limits of a published load, working up from starting, keeping an eye out for stiff bolt lifts or sticky extractions (possible pressure signs), and you're good.
Why would IMR4831 cause pressure problems? Stick to the limits of a published load, working up from starting, keeping an eye out for stiff bolt lifts or sticky extractions (possible pressure signs), and you're good.
I called Speer regarding the Deep Curl bullets and load data advice. The tech I talked to said that Speer didn't recommend loading bullets for applications they hadn't tested. The problem is that the heavily plated - yes they are indeed plated - bullets had a tendency to go from safe loads to ones that could be severely overpressure with small powder increases with no warning signs.
nowarningshot
CGN Ultra frequent flyer
I just take the advice from Speer as a CYA mentality, in the age of litigation. I like Litnut's advice, if you start at a starting load and work up slowly. Many times your accuracy sweet spot is not at a max load powder charge. Deer and Moose are not going to come running up and ridicule someone with print outs from their chrony's. Lots of animals killed with 303 and 30-30 which are certainly not sprinters, nor do they usually use a premium projectile like the deep curl.
The Outsider
CGN Regular
I've used DeepCurls with great results,
only briefly though with a 7mm and IMR7828 before I sold the rifle.
I still use 180 gr 30 Cal DeepCurls in my 300WM.
I heard they don't make them any more due to the possible erratic pressure issues.
only briefly though with a 7mm and IMR7828 before I sold the rifle.
I still use 180 gr 30 Cal DeepCurls in my 300WM.
I heard they don't make them any more due to the possible erratic pressure issues.
