+1 on handloading, and + 1 on the muzzle brake
. All advice given is excellent, but i would start with the handloading first as you may not need to do anything else. plus, before long, you will be saving money. we recently bought my nephew the same gun you mentioned, and they threw in a box of 150 grain level one loads. the gun shot between 1.5-2" groups. We then tried a group with each of our handloads and found one that shoots just under an inch.
we have two of these guns with brakes on them and two that do not. the defensive edge brakes are incredible! the other two will have brakes, its just a matter of time. without the brake i have to have a slight to moderate hold on the front of the gun, with the brake i can squeeze the rear bag and shoot. We have done nothing else (except trigger jobs, they are a must in my opinion) to these 4 guns and they will all shoot an inch or better after finding the right loads. the ones with brakes are alot easier to consistently shoot under an inch. not sure it makes the gun shoot better, but it helps me to shoot the gun better. good luck.