`

338 Terminator

 

You have entered the home of data for the Terminator family of cartridges. Like all loading data this is just a guideline to help you and not absolute information. This is simply what worked for us in just one or two rifles with our lot of powder, bullets primers etc. It is still your responsiblity to follow safe loading practices and make your own safety decisions.  It is not a safe loading practice to take your rifle chambered in one of these rounds even though we built it and simply start with the max load. It is still a required practice that you safely work up to a safe pressure and load. Load date can change from lot to lot with components, ambient temperature or any other number of factors. Please be safe and use this info as a guideline. Have fun and good shooting.

 

Shawn 

 

 338 Terminator

 

 

Notes about the 338 Terminator:

 

 

1.    Most upper end loads have to use a drop to to put the powder in the case to keep from having seating issues and proper controlling of the OAL.

 

2.    No matter what powder we tried with the 300 gr OTM bullets the seating depth hung in the -.005 to -.015" range.

 

3.    We have properly headstamped brass made and fully formed at the shop.

 

4.    Our case dimensions are not the same as 338 LM Ackley Improved.

 

5.    During initial testing we got the really good results from RL 33 shown below. Since then we have seen some pretty big lot to lot variations with RL 33. Some variations were big like reaching pressure at 101.0 grains and predictably going very slow. Keep an eye on this and be carefull with it.

 

 

 

300 gr. Berger OTM

 

Case: DE 338 Terminator

Case Capacity Formed: 125.6 gr H2O

Max Case Length: 2.740"

Trim Length: 2.730 "

Primer: CCI 250

Bullet: Berger 300 gr. OTM

Max OAL to Lands: 3.935"

Test Barrel: Hart LRKM Profile, fluted, 1-9 twist, 30" finished length, standard bore & groove diameters

 

Powder: VV N570

Max Charge: 108.0 gr (left faint ejector marks & very light bolt lift)

 

Best Load: 107.0 gr VV - N570, OAL 3.930" (-.005" off lands)

Performance: 3 shots @ 100 yards .192", ES 6 fps, ave velocity 3124fps

 

 

 

300 gr. Berger OTM

 

 

Case: DE 338 Terminator

Case Capacity Formed: 125.6 gr H2O

 

Best Load: 110.0 gr RL 33, OAL 3.930" (-.010" off lands)

Performance: 3 shots @ 100 yards .227", ES 9 fps, ave velocity 3104 fps

 

 

Max Case Length: 2.740"

Trim Length: 2.730 "

Primer: CCI 250

Bullet: Berger 300 gr. OTM

Max OAL to Lands: 3.935"

Test Barrel: Hart LRKM Profile, fluted, 1-9 twist, 30" finished length, standard bore & groove diameters 

 

Powder: RL 33

Max Charge: 112.0 gr (left faint ejector marks & very light bolt lift)

 

All Terminator series rounds are improved rounds with our patented +P throating technology. As such the brass for these rounds must be fire formed prior to loading. Once the brass is formed, loading and load development may proceed in a normal manner. Here is what we recommend:

 

1. Purchase formed brass from us and you are done, go straight to step # 8

 

2. If you choose to form brass yourself get the parent case prepped and primed.

 

3. Load the appropriate powder and forming charge (see below).

 

4. Add cornmeal or grits to take up space in the case, do not shake while doing this as it mixes the powder and cornmeal together. Fill until the case is full all way up the neck.

 

5. Take a small piece of paper towel or tissue and plug the mouth of the case. Take care not to over pack as this can cause higher than normal pressures. It should be just enough to keep the corn meal and powder tight and not shift around.

 

6. Now in a safe place (shooting range) fire the round through the rifle. The paper patch could be a potential fire hazard in certain conditions use caution here. Now fired, the case is 98-99% formed, the shoulder should be forward but not completely sharp at the edges.

 

7. Clean the chamber and barrel of debris every 5 rounds or so, this doesn’t require a full tear down cleaning but a removal of the chunks of filler. This is also a good time to let the barrel cool down. You do damage to your barrel anytime you shoot it hot even when there is no bullet going down it.

 

8. Now that your Terminator brass is formed you are ready to resize it and start normal loading procedures.

 

The following forming loads are used with filler and a paper patch as described above.

 

338 Terminator                 25.0 gr Winchester Super Field

300 Terminator                 25.0 gr Winchester Super Field

260 Terminator                 15.0 gr Winchester Super Field